256+ tools · 15 categories · REST API live · CLI coming soon
Run any tool from your terminal via npx. No install required.
Image processing, AI-assisted regex, DNS propagation checker, and more in the pipeline.
Validate a credit card number via the Luhn checksum and detect its network (Visa, Mastercard, American Express, Discover, Diners Club, JCB, Maestro, UnionPay) from its prefix and length
Convert text to ASCII art with multiple font styles and borders
Generate a content-hash ETag response header value using MD5, SHA-1, or SHA-256, with strong or weak (W/) validator syntax, ready to drop into a server response.
Generate SVG illustrations, icons, and graphics from a text description using GPT-4o
Build a Permissions-Policy (formerly Feature-Policy) response header from a list of browser features and their allowlists (self, none, specific origins, or all origins), with a plain-English note on what each directive restricts, or parse an existing header
Paste a function or class and get a documentation comment written in the idiomatic style for its language, JSDoc, a Google-style Python docstring, Javadoc, rustdoc, and similar, plus the original code with the comment inserted above it.
Format, validate, and minify JSON
Compare two JSON objects and highlight differences
Generate TypeScript interfaces from JSON
Generate Zod schemas from JSON
Convert JSON arrays to CSV format
Test JSONPath expressions on JSON data
Minify and format JSON with size stats
Validate JSON data against a JSON Schema Draft-7
Describe your data in plain English: get a production-ready JSON Schema (Draft-07) instantly, powered by GPT-4o mini
Flatten deeply nested JSON to dot-notation keys, or unflatten a flat object back into nested structure.
Deep merge two JSON objects: choose deep merge, shallow, or replace-arrays strategy. Shows conflicts.
Fix malformed JSON: unquoted keys, single quotes, trailing commas, comments, undefined values, and unclosed brackets
Generate Go struct definitions from JSON with proper field names and json tags
Generate Python TypedDict, dataclass, or Pydantic models from JSON
Resolve an RFC 6901 JSON Pointer (like /users/0/name) against a JSON document, with clear handling of ~0/~1 escapes and missing targets.
Convert a JSON Schema document into TypeScript interfaces and types
Apply an RFC 7396 JSON Merge Patch document to a target JSON document and return the merged result, with null-valued keys in the patch removing the corresponding target key.
Encode and decode Base64 strings
Percent-encode and decode URLs
Encode and decode HTML entities
Inspect and convert Unicode code points
Generate secure passwords with custom length, charset, and strength check
Escape and unescape strings for JSON, JavaScript, HTML, URL, and CSV
Convert text to Morse code and decode Morse back to text
Encode and decode Base32 with Standard, Extended Hex, Crockford, and z-base-32 alphabets
Generate QR codes for URLs and text with custom error correction
Encode and decode text as Base58 (Bitcoin-address style) or Base62 (alphanumeric, URL-safe)
Calculate a password's actual entropy in bits and estimated crack time
MD5, SHA-1, SHA-256, SHA-512 and more
Hash and verify bcrypt passwords
Generate Apache .htpasswd entries with bcrypt, SHA-1, MD5, or plain password hashing
Hash and verify passwords with scrypt, a bcrypt-alternative memory-hard KDF
Generate Subresource Integrity (SRI) hashes for a script or stylesheet: SHA-256, SHA-384, and SHA-512, ready to drop into an HTML integrity attribute.
Decode and inspect JWT tokens
Sign JWTs with HS256/RS256
Parse a JSON Web Key Set (JWKS) or a single JWK and view each key's type, use, algorithm, key ID, and size in a readable table
Build a JWT header and payload preview with standard claims — unsigned, pair with JWT Signer to sign it
Compute the RFC 7638 thumbprint of a JSON Web Key: canonicalize its required members and hash them with SHA-256, SHA-384, or SHA-512.
Test regular expressions with live matching
Complete regex reference with live pattern tester
Describe what you want to match in plain English: get a regex pattern, explanation, and test cases powered by GPT-4o mini
Paste any regex pattern and get a plain-English, token-by-token breakdown of what it matches, powered by GPT-4o mini
Compare two text blocks line by line
Live preview Markdown as HTML
Generate placeholder text
Convert between camelCase, snake_case, kebab-case and more
Count words, characters, lines and reading time
Convert text to URL-friendly slugs with custom separators
Sort, deduplicate, reverse, shuffle, and transform text lines
Convert HTML to Markdown and Markdown back to HTML
Convert text to ASCII art with multiple font styles and borders
Analyze text for word count, readability scores, and word frequency
Convert numbers to English words, ordinals, and Roman numerals
View and generate unified diffs with colored added/removed line highlighting
Flag sentences written in passive voice and see the exact phrase that triggered each match
Score pasted text with Flesch Reading Ease, Flesch-Kincaid Grade Level, and Gunning Fog Index
Scan text for filler words, hedge phrases, and clichés with per-phrase counts and an overall density score
Compute the edit distance and similarity ratio between two strings
Get a histogram of sentence lengths plus mean, median, and standard deviation, a signal distinct from readability grade scores
Search emoji by name or keyword and get back the character, its Unicode code point, and its GitHub-style shortcode.
Count keyword and phrase frequency and density across a block of text, the way an SEO keyword-density checker does
Minify and beautify CSS
Visual CSS gradient builder with linear, radial, and conic support
Visual CSS box-shadow builder with multiple layers and presets
Write CSS and see it applied to sample HTML elements live
Visual CSS border-radius builder with live preview and presets
Convert px to rem, em, pt, vw and more with configurable base font size
Visual CSS flexbox builder with live preview and generated CSS
Visual CSS grid layout builder with live preview and presets
Paste any CSS and get a plain-English breakdown of every selector and property: powered by GPT-4o mini
Calculate and compare CSS selector specificity with token breakdown
Visual cubic-bezier animation curve generator with presets and SVG preview
Generate fluid CSS clamp() values for responsive typography and spacing
Build CSS @keyframes animations with presets, live preview, and generated CSS
Convert px values to viewport units (vw, vh) for responsive design
Pick and convert between HEX, RGB, HSL, HSV
Generate harmonious color palettes
Convert colors between HEX, RGB, HSL, and HSV formats
Generate tints and shades scale from any base color with CSS variable output
Blend two colors with intermediate steps and explore complementary/analogous/triadic relationships
Check WCAG 2.1 color contrast ratios for accessibility compliance
Generate v1, v4, v5, and v7 UUIDs
Generate Universally Unique Lexicographically Sortable Identifiers
Build cURL commands from URL, method, headers, and body
Reference guide for all HTTP status codes with search and category filter
Convert cURL commands to fetch, axios, Python, Go, PHP, and Ruby
Calculate subnet info, host ranges, and split subnets from CIDR notation
Generate CORS headers with nginx, Express, and Apache config snippets
Build Content-Security-Policy headers with presets and validation
Searchable reference for 80+ HTTP request and response headers
Browse and explore OpenAPI/Swagger specs with endpoint search
Build and test HTTP requests with headers, body, and auth
Compare two API responses or JSON payloads side by side
Parse URLs into components and build/modify URLs with query params
Convert IPv4 addresses between decimal, hex, binary, octal, and integer formats
Look up DNS records (A, AAAA, MX, TXT, NS, CNAME and more) via DNS-over-HTTPS
Geolocate any IPv4/IPv6 address: country, city, ISP, coordinates, and timezone
Inspect SSL/TLS certificates: expiry, issuer, SANs, and fingerprint for any domain
Validate email addresses: format check, MX record lookup, and disposable provider detection
Parse a browser DevTools .har network export into a readable table of requests, status codes, timing, and sizes
Validate a sitemap.xml or sitemap index against the sitemaps.org protocol: required tags, absolute URLs, valid changefreq/priority/lastmod values, and duplicate entries
Parse a robots.txt file into User-agent groups and flag directive syntax mistakes: rules before any User-agent, unknown directives, non-absolute Sitemap URLs, malformed Crawl-delay values, and duplicate rules
Parse a browser User-Agent string into browser, engine, OS, and device type
Build and explain an HTTP Cache-Control response header from directives like max-age, s-maxage, no-store, and immutable
Expand an IPv6 address to its full 8-group form or compress it to its RFC 5952 canonical shortest form, and classify its address type
Build a Referrer-Policy header value from one or more policy tokens with a plain-English explanation of each and warnings for risky choices like unsafe-url
Build an HTTP Link response header from URL/rel pairs (preload, preconnect, prefetch, canonical, pagination) with as/type/crossorigin attributes and a plain-English explanation of each entry
Parse a Set-Cookie header and validate its attribute combination: SameSite=None requires Secure, __Host-/__Secure- prefixes have their own required attributes, and a missing Secure or overly long Max-Age gets flagged.
Parse a raw email header block into structured From/To/Subject fields, the Received hop chain, and SPF/DKIM/DMARC results from an Authentication-Results header.
Generate a content-hash ETag response header value using MD5, SHA-1, or SHA-256, with strong or weak (W/) validator syntax, ready to drop into a server response.
Build an HTTP Range request header from byte ranges (explicit, open-ended, or last-N-bytes), and parse a server's Content-Range response to verify what it actually sent back.
Build a Vary response header from the request headers a response varies by (Accept-Encoding, Accept-Language, Authorization, etc.), with a plain-English note on the caching implication of each, or parse an existing Vary header to explain it.
Validate a web app manifest.json against the W3C Web App Manifest spec's installability requirements: name/short_name, start_url, display mode, and an icons array covering a 512x512 and a maskable icon
Build a Permissions-Policy (formerly Feature-Policy) response header from a list of browser features and their allowlists (self, none, specific origins, or all origins), with a plain-English note on what each directive restricts, or parse an existing header
Build an Accept-CH (and optional Critical-CH) response header from a list of Client Hints your server wants the browser to send, with a plain-English note on what each hint reveals, or decode raw Sec-CH-* request headers into their real values
Build or parse a Content-Disposition header for a file download or inline display, with RFC 5987 support for non-ASCII filenames.
Split a URL list exceeding the sitemaps.org 50,000-URL cap into multiple sitemap.xml files plus a sitemap index file
Build the X-Content-Type-Options: nosniff response header (there is only one valid value) with a plain-English explanation of the MIME-sniffing attack it prevents, validate a pasted header value, and check how risky a given Content-Type is to serve without it
Build an Accept-Language request-header value from locale/quality pairs, sorted by preference, or parse an existing header into its ranked locale/quality entries
Generate a cryptographically random base64 nonce for a Content-Security-Policy script-src/style-src directive, with a ready-to-paste header snippet and matching <script nonce="...">/<style nonce="..."> tag.
Build an HTTP Prefer request-header value from a list of preferences with optional values and parameters, or parse an existing one, per RFC 7240
Build a Retry-After response header from a delay in seconds or a target date/time, or parse an existing one, per RFC 9110
Parse and explain cron expressions
Convert Unix timestamps to/from human-readable dates
Calculate the difference between two dates in years, months, weeks, and days
Convert times between world timezones using the Intl API
Preview the next N scheduled run times for any cron expression
Parse an ISO 8601 duration like P3DT4H30M into its components and total seconds, or format a number of seconds back into a canonical duration string.
Format numbers with Intl.NumberFormat: locale, currency, percent, scientific
Calculate and convert aspect ratios, scale dimensions, and fit/cover boxes
Convert between binary, octal, hex, and decimal
Validate a credit card number via the Luhn checksum and detect its network (Visa, Mastercard, American Express, Discover, Diners Club, JCB, Maestro, UnionPay) from its prefix and length
Validate an IBAN via the mod-97 checksum (ISO 13616) and format it into readable grouped blocks
Compute monthly payment, total interest, and a full amortization schedule from principal, rate, and term
Add or remove VAT or sales tax from a price in either direction, net to gross or gross to net, given a rate
Compute future value from principal, annual rate, compounding frequency, and an optional recurring contribution, with a year-by-year breakdown
Calculate a tip and split the bill and tip evenly across any number of people
Compute simple (non-compounding) interest and total payoff from principal, annual rate, and term
Convert between present and future value at a given rate: grow a present sum to its future value, or discount a future sum back to today.
Compute the percentage increase or decrease between two numbers, plus the absolute change, direction, and multiplier.
Convert between a nominal annual rate (APR) and the effective annual yield (APY) for a given compounding frequency, in both directions.
Given any two of cost, selling price, gross margin percent, and markup percent, solve for the other two plus the gross profit
Work out a sale price, the amount saved, or the discount percent from any one of them, and stack successive discounts correctly
Calculate the unit count and revenue at which a business breaks even
Calculate the video file size from a target bitrate and duration, or the required bitrate to hit a target file size, with an optional separate audio bitrate.
Estimate how many years it takes an investment to double at a given rate, or the rate needed to double in a given number of years, using the Rule of 72 shortcut compared against the exact logarithmic result
Compute the equated monthly installment, total interest, and a year-by-year breakdown for a loan from principal, rate, and tenure
Calculate how long it takes to reach a savings goal at a fixed monthly contribution, or how much you need to save each month to hit a goal by a target date
Compute return on investment percent from an initial and final value, plus the annualized return given an optional holding period in years.
Compare two or more package options by price and quantity to find the true cost per unit and flag the cheapest.
Break a cash total down into the minimum count of bills and coins from a set of denominations, or compute change owed and its breakdown from an amount due and amount tendered.
Given an initial investment and a series of periodic cash flows, compute the simple payback period and the discounted payback period, the point where cumulative cash flow turns positive
Compute a CD's maturity value and effective annual yield (APY) from a principal, nominal annual rate, term in months, and compounding frequency, plus the net payout if withdrawn early
Build a year-by-year depreciation schedule for a fixed asset using straight-line, double-declining-balance, or sum-of-years-digits
Round a cashless total to the nearest payable cash denomination, the way a till rounds a card-priced total to the nearest 5 cents when settling in physical cash, with round-nearest, round-up, and round-down modes
Compute SMA and EMA series from a list of numbers and a window size, a foundational technical-indicator building block for price or volume data
Compute a weighted GPA from a list of courses, each with a letter grade and credit hours, using the standard 4.0-capped scale
Compute per-account and overall credit utilization (balance divided by limit) from one or more credit accounts, plus a qualitative tier matching common credit-scoring guidance.
Compute the debt-to-income ratio (total monthly debt payments over gross monthly income) from one or more monthly debts, plus a qualitative tier matching common mortgage-lending guidance.
Compute the single weighted-average interest rate across a list of loan balances (e.g. credit cards or student loans considered for consolidation), plus total balance and combined monthly and annual interest accrual
Solve for the minimum hourly rate a freelancer must charge to hit a target annual income, given billable hours, weeks worked, overhead, and a profit margin
See how much sooner a loan pays off, and how much interest you save, by adding a fixed extra amount to every monthly payment
Generate SVG favicons from text with custom colors and shapes
View, analyze, sanitize, and optimize SVG files
Generate SVG illustrations, icons, and graphics from a text description using GPT-4o
Compress JPEG, PNG, and WebP images in the browser using Canvas with quality and resize controls
Convert images between JPEG, PNG, and WebP formats entirely in the browser
Read format, dimensions, bit depth, and alpha channel from image file bytes: no decoding required
Read camera make/model, orientation, timestamps, exposure settings, and GPS coordinates directly from a JPEG's EXIF data
Read how many images a .ico file embeds and each one's dimensions, color depth, and size directly from its header bytes
Inspect a GIF file's frame count, animation duration, and loop count directly from its block structure, without decoding pixel data.
Format and minify HTML with configurable indentation
Parse and validate .env files with duplicate detection and format conversion
Parse, compare, and check semantic version ranges
Format and minify SQL with keyword uppercasing and dialect detection
Build git commands from a form: commit, push, branch, and more
Describe a terminal task in plain English: get the exact shell command with a breakdown of every flag, powered by GPT-4o mini
Generate and preview Open Graph and Twitter card meta tags
Convert between octal, symbolic, and descriptive Unix file permissions
Parse docker image references into registry, namespace, tag, and digest components
Minify HTML by removing comments, collapsing whitespace, and stripping empty attributes
Minify JavaScript by removing comments, collapsing whitespace, and stripping console calls
Generate HTML and Markdown tables from CSV, TSV, or pipe-delimited data
Format and minify XML with validation
Format and minify GraphQL queries and mutations
Paste a git diff and get a Conventional Commits-style commit message back: type, scope, subject, and body, powered by GPT-4o mini
Compare a .env file against its .env.example template to flag keys missing from either side
Validate EAN-13, EAN-8, and UPC-A barcode numbers via their weighted mod-10 check digit algorithm
Paste an error stack trace and get the likely error type, a plain-English explanation of the cause, and a suggested fix, powered by GPT-4o mini
Validate an ISBN-10 or ISBN-13 checksum and convert a valid ISBN to the other format where possible
Look up the MIME type for a file extension, or the file extension(s) for a MIME type
Parse a GitHub URL (repo, pull request, issue, commit, or file with line range) into structured components
Scan a regex for catastrophic-backtracking (ReDoS) risk: nested quantifiers, overlapping alternation, and adjacent overlapping quantifiers
Describe your app in plain English and get a production-ready Dockerfile back, with multi-stage builds, layer caching, and a non-root user, powered by GPT-4o mini
Paste a SQL query and get a plain-English explanation of what it returns, how it is evaluated step by step, which tables it touches, and what to check for performance, powered by GPT-4o mini
Paste a compiler, linker, or package-manager error message and get a plain-English explanation, the usual root causes, and a concrete next step, powered by GPT-4o mini
Split a Markdown document into its YAML front matter fields and body content
Lint a git commit message against the Conventional Commits v1.0.0 spec: header format, blank-line separation, footer tokens, and BREAKING CHANGE casing
Scan a Markdown document's ATX headings and build a nested table of contents with GitHub-style anchor slugs, disambiguating duplicate headings automatically
Paste a .gitignore file and a list of file paths, and see which paths would be ignored, matching gitignore glob semantics including negation patterns (!) and directory-only rules.
Paste CSV data and a table name to get parameterless SQL INSERT statements back, with basic type inference and identifier quoting.
Find duplicate rows in CSV or TSV data by comparing the whole row or a chosen set of key columns, and see exactly which data rows each duplicate group appears at.
Paste a function or class and get a documentation comment written in the idiomatic style for its language, JSDoc, a Google-style Python docstring, Javadoc, rustdoc, and similar, plus the original code with the comment inserted above it.
Paste a function and get back a set of proposed unit test cases, concrete inputs, expected outputs, and whether each covers a happy path, edge case, or error case, powered by GPT-4o mini
Parse a Markdown document's checkbox task list and report completion percentage overall and per section, grouped by the nearest preceding heading
Paste a git diff and get back a structured pull request description: a title, a bulleted summary of what changed, and a test plan checklist, powered by GPT-4o mini
Parse an .editorconfig file into its root flag and glob sections, and flag structural mistakes: unknown properties, invalid values for known properties, a root declaration outside the preamble, and duplicate properties within a section
Parse a tsconfig.json file as JSONC and flag structural mistakes: unknown top-level keys, unknown compilerOptions keys, wrong value types, and malformed files/include/exclude/references/paths
Parse a package.json's exports map and flag common dual-package (ESM/CJS) misconfigurations: a types condition not listed first, a missing default fallback, mismatched require/import extensions, mixed subpath and condition keys, and a subpath pattern with no matching *
Parse CSV or TSV data and infer each column's data type (integer, float, boolean, ISO 8601 date, or string), flagging which columns are nullable and how many empty cells each one has.
Paste a shell or bash command and get a plain-English, flag-by-flag breakdown of what it does, plus a warning if it's destructive, powered by GPT-4o mini
Convert between bytes, KB, MB, GB, TB in both SI and binary units
Validate YAML syntax with detailed error messages and stats
Generate random names, emails, UUIDs, dates, and more
Parse and view CSV files as a table or JSON with delimiter detection
Format, validate, and convert TOML to/from JSON
Auto-detect and format API responses: JSON, XML, HTML, CSV
Convert XML to JSON and JSON back to XML with attribute handling
Parse and convert INI/config files to JSON and back, with section browsing
Format, validate, and convert newline-delimited JSON (NDJSON/JSON Lines), one JSON value per line
Convert between YAML and JSON
Read title, author, creation date, PDF version, page count, and encryption flag directly from a PDF's trailer/Info dictionary
Read sample rate, channel count, bit depth, and duration directly from a WAV file's RIFF/fmt/data chunk headers
Read title, artist, album, year, genre, comment, and track number directly from an MP3 file's ID3 tags
Convert subtitles between SubRip (.srt) and WebVTT (.vtt), with an optional time shift to resync every cue
Read sample rate, channels, bit depth, total samples, and duration from a FLAC file's STREAMINFO block, plus Vorbis comment tags like artist, title, and album, without decoding any audio
Read duration, resolution, and video/audio codec identifiers from an MP4 or WebM file's container header, without decoding any frames or transcoding
List each page's width, height, rotation, and orientation directly from a PDF's page tree, and flag common paper sizes like Letter or A4
Expand YAML anchors, aliases, and merge keys inline, and list which anchors were referenced vs. left unused
Parse an SRT or WebVTT file and report the words-per-minute reading speed of every cue, flagging ones that exceed common broadcast accessibility guidelines.
Remove duplicate records from newline-delimited JSON (NDJSON/JSON Lines), either by exact structural equality or by a chosen key field, keeping the first occurrence
Estimate token count and API cost for any text across GPT-4o, Claude, Gemini, and more
Detect and redact personally identifiable information: emails, phones, SSNs, credit cards, IPs, IBANs, and crypto wallets
Scan code or config for leaked API keys, tokens, and credentials: OpenAI, AWS, GitHub, Stripe, and more
Detect prompt injection and jailbreak attempts in user-provided input before passing to an LLM
Truncate text or prompts to a token budget: keep start, end, or middle. Essential for fitting context into LLM windows.
Split documents into overlapping chunks for RAG pipelines: by sentence, paragraph, or fixed size with configurable overlap.
Extract all URLs and links from text or HTML: includes protocol, domain, and path breakdown.
Strip HTML tags, scripts, styles, and event handlers to produce clean text for LLM ingestion.
Validate any JSON value against a JSON Schema (Draft-07): types, required fields, patterns, formats, and nested rules.
Pull JSON blocks out of mixed LLM output: handles markdown code blocks and inline JSON objects/arrays.
Remove duplicate lines from text: exact, case-insensitive, trimmed, or normalized matching. Useful for RAG dedup.
Extract top keywords and phrases from text using TF-IDF scoring: useful for tagging, indexing, and RAG metadata.
Structurally diff two JSON objects and return a flat list of added, removed, changed, and unchanged paths: designed for AI agent pipelines.
Extract HTML tables into JSON arrays with headers and rows. Parse any HTML page for tabular data.
Detect emails, phones, dates, IPs, credit cards, IBANs, currencies, hashtags, and mentions from text.
Strip scripts, styles, comments, classes, and whitespace from HTML to minimize token usage before LLM ingestion.
Normalize and compress markdown: strip frontmatter, collapse blank lines, remove comments to reduce token count.
Remove nulls, empty arrays, empty objects from JSON to reduce token footprint before sending to an LLM.
Score and rerank text chunks by relevance to a query using TF-IDF. Drop irrelevant chunks before LLM context.
Score a single text passage against a query. Returns a 0-1 relevance score, grade, matched terms, and coverage.
Expand a search query with synonyms and stemmed variants to improve retrieval recall in RAG pipelines.
Extractive summarization: pick the most informative sentences to fit within a token budget for LLM context windows.
Compute cosine similarity, dot product, and Euclidean / Manhattan distance between two embedding vectors, right in the browser.
Turn a list of input/output example pairs into a numbered, XML-tagged, or delimiter-separated few-shot prompt template
Lint an LLM tool/function-calling JSON definition (OpenAI, Anthropic, or MCP format) for mistakes that measurably hurt model accuracy: missing descriptions, invalid names, empty enums, or a required field with no matching property