JSON Formatter and Validator
Format JSON and explore a collapsible object tree.
Developer tools
Everyday helpers for code and configuration. Format and validate JSON, encode or decode Base64 and URLs, escape HTML entities, read a JWT, convert number bases, or generate unique identifiers. Inputs are handled in the browser, so tokens and sample payloads stay with you.
85 tools in this part of the catalogue.
Showing 1-48 of 85 tools, page 1 of 2
Featured Developer tools
Password Generator
Generate random passwords or word passphrases in your browser.
Formatters and validators10 tools
JSON Formatter and Validator
Format JSON and explore a collapsible object tree.
XML Formatter
Format, minify or check one XML document.
YAML and JSON Converter
Convert one YAML document to JSON, or JSON back to YAML.
SQL Formatter
Reformat SQL with a chosen dialect and keyword case.
JSON to TypeScript
Generate typed models from JSON or CSV samples.
Code Beautifier
Format code in seven languages without running it.
JSON Diff and Patch
Compare two JSON documents and copy the RFC 6902 patch.
Streaming NDJSON Validator
Validate an NDJSON file line by line.
Unified Patch Inspector
Review patch hunks and test their exact source context.
Dockerfile and Compose Linter
Review Dockerfile and Compose configuration warnings.
Encode and decode5 tools
Base64 Encoder and Decoder
Encode text or a file as Base64, or decode it back.
URL Encoder, Decoder and Query Editor
Encode, decode and edit the parts of a web address.
HTML Entity Encoder and Decoder
Write ampersands and angle brackets as character references.
Multi-Codec Text Encoder and Decoder
Convert text with named Base32, Base58 and byte codecs.
String Escape and Unescape Tool
Escape and recover text for a named string context.
Test and debug2 tools
Regex Tester
Test a JavaScript regular expression against sample text.
Cron Expression Explainer
Build cron expressions and preview their next runs.
Inspect and convert8 tools
JWT Decoder and Claims Inspector
Read a JWT header and payload, with claims shown as dates.
Number Base Converter
Convert a signed whole number between bases 2 and 36.
Subnet and CIDR Calculator
Work out the network, host range and mask for an IPv4 or IPv6 prefix.
Chmod Calculator
Turn read, write and execute choices into chmod modes.
MIME Type and File Signature Checker
Check file bytes against their extensions.
Semver Comparator and Range Explainer
Compare semantic versions and test a range.
HTTP Status Code Reference
Look up HTTP codes in a dated IANA registry snapshot.
SPDX License Metadata Lookup
Find SPDX identifiers and supplied license metadata.
Generators5 tools
UUID, ULID and NanoID Generator and Validator
Create test identifiers in four formats and check a value.
cURL Command Builder
Build a cURL command and matching request snippets.
Conventional Commit Message Builder
Build or check a conventional commit message.
Regex to Code Snippet Generator
Quote a regex pattern for eight programming languages.
gitignore Generator
Combine curated ignore rules for your project.
Color and CSS9 tools
Color Picker and Converter
Pick a color and copy its HEX, RGB and HSL values.
Contrast Checker
Check text and background colors against WCAG 2.2 contrast thresholds.
CSS Gradient Generator
Build a linear, radial or conic gradient and copy the CSS.
Box Shadow Generator
Build a box shadow, preview it and copy the CSS.
Aspect Ratio Calculator
Find the missing width or height in a width-to-height ratio.
CSS Unit Converter
Convert CSS units with explicit font and viewport sizes.
CSS Grid Layout Generator
Build a CSS grid, preview it and copy the code.
CSS Named Color Reference
Find CSS color names, hex values and nearby colors.
CSS Text Shadow Generator
Create layered text shadows and copy the CSS.
More Developer tools
CSV/JSON Converter
Convert CSV, TSV, JSON, XML and Excel tables both ways.
Password Generator
Generate random passwords or word passphrases in your browser.
Colour Picker from Image
Read any image pixel's color and copy HEX, RGB and HSL.
Hash and Checksum Generator
Hash text or files and compare a supplied checksum.
Unix Timestamp Converter
Convert Unix timestamps and inspect ISO dates and offsets.
GCD and LCM Calculator
Find the greatest common divisor and least common multiple.
Digital Storage Converter
Convert bits and bytes with named decimal or binary storage units.
Password Strength Checker
Get a local, dictionary-based estimate of a password's strength.
Image Palette Extractor
Extract image colors and download JSON, CSS or a palette strip.