Developer Tools

API Rate Limit Header Parser

Quick, free API Rate Limit Header Parser in your browser

Code Snippet Version Diff

Quick, free Code Snippet Version Diff in your browser

Curl Command Generator

Quick, free Curl Command Generator in your browser

Env Var Naming Linter

Quick, free Env Var Naming Linter in your browser

Extension Permission Explainer

Quick, free Extension Permission Explainer in your browser

Feature Flag Config Diff

Quick, free Feature Flag Config Diff in your browser

Focus Indicator Tester

Quick, free Focus Indicator Tester in your browser

GraphQL Schema Visualizer

Quick, free GraphQL Schema Visualizer in your browser

gRPC Request Builder

gRPC request builder: get a ready-to-run grpcurl command

INI File Parser

Parse INI files to JSON, with duplicate warnings

JSON Array Sorter

Quick, free JSON Array Sorter in your browser

JSON to SQL Schema Generator

Quick, free JSON to SQL Schema Generator in your browser

Kotlin Code Formatter

Quick, free Kotlin Code Formatter in your browser

Kubernetes YAML Validator

Quick, free Kubernetes YAML Validator in your browser

METAR Decoder

Quick, free METAR Decoder in your browser

Nested JSON Flattener

Quick, free Nested JSON Flattener in your browser

Newton's Method Visualizer

Quick, free Newton's Method Visualizer in your browser

OpenAPI Spec Visualizer

Quick, free OpenAPI Spec Visualizer in your browser

package.json Script Explainer

Quick, free package.json Script Explainer in your browser

Postman Collection Viewer

View and search Postman collections in your browser

REST to GraphQL Mapper

Quick, free REST to GraphQL Mapper in your browser

Rust Struct Generator

Quick, free Rust Struct Generator in your browser

Semver Range Tester

Quick, free Semver Range Tester in your browser

Severance Package Calculator

Quick, free Severance Package Calculator in your browser

T-Test Calculator

Quick, free T-Test Calculator in your browser

Terraform HCL Formatter

Quick, free Terraform HCL Formatter in your browser

TOML Formatter & Validator

Quick, free TOML Formatter & Validator in your browser

Family Tree Builder

Quick, free Family Tree Builder in your browser

Game Server Tick Rate Explainer

Quick, free Game Server Tick Rate Explainer in your browser

SQL Explain Plan Visualizer

Turn query plans into a readable tree

Service Worker Generator

Build a starter service worker quickly

HTML Code Editor

HTML code editor with live preview and console

Punycode to Unicode

Decode punycode domains into readable Unicode labels

Decode Quoted Printable

Decode quoted-printable email text

SVG Wave Generator

Generate decorative wave section dividers

CSS Clip Path Maker

Draw polygon clip paths visually

HTML Entity Encoder

Escape and decode HTML characters

Lorem JSON Generator

Generate realistic mock JSON payloads

Binary Hex Decimal Converter

Convert between number bases instantly

Gitignore Generator

Build .gitignore files by tech stack

Nginx Config Generator

Generate server block configs from a form

Webpack Config Generator

Create a starter webpack setup

Docker Image Size Estimator

Estimate container footprint before build

Glob Pattern Tester

Preview glob matching for candidate file paths

JSON Viewer

Explore JSON data clearly

Embed Code Generator

Embed code generator for iframe and video links

Touchscreen Test

Check touch support and gesture response

What Is My Browser

See your browser and device details

URL Parser

Break a URL into its parts, copy any field

Sitemap Generator

Turn a list of URLs into a ready-to-upload XML sitemap

JSON Formatter

Pretty-print, validate, and minify JSON

Meta Tag Generator

Generate SEO and social meta tags

YAML Validator

Lint YAML files and catch indent errors

CSS Formatter

Beautify and organize stylesheets

HMAC Generator

Compute keyed HMAC signatures

ASCII Table Reference

Interactive searchable ASCII chart

SVG Blob Generator

Random organic blob shapes for design

Mock API Response Builder

Generate mock JSON API responses from a field list

License Chooser

Answer three questions, get a suggested open-source license

Open Graph Previewer

Preview how your link looks when shared

CSS Cubic Bezier Editor

Drag-and-drop editor for CSS timing functions

XML Formatter

Beautify and validate XML documents

SQL Formatter

Beautify SQL queries with keyword casing

Hash Generator

MD5, SHA-1, SHA-256 hashes of text

Docker Run to Compose

Convert docker run commands to compose files

Regex Tester

Test regular expressions with live matches

JWT Decoder

Decode JWT headers and payloads locally

Regex Cheat Sheet

Interactive regex reference with examples

CSS Grid Generator

Visually design grids and copy the CSS

CSS Minifier

Compress CSS files for faster loads

JSON Minifier

Strip whitespace for smaller payloads

Checksum Verifier

Verify file integrity against a hash

HTTP Status Code Reference

Searchable HTTP status code explanations

Unicode Character Inspector

Inspect every character's codepoints in text

Semver Checker

Compare and validate semantic versions

HTML Boilerplate Generator

Custom HTML5 starter templates

CSS Filter Playground

Preview CSS filters on sample images

Keyboard Event Tester

Keyboard event tester with a log and copy JSON

JWT Encoder / Decoder

Decode and mint HS256 JWTs

Diff Checker

Side-by-side code diff with syntax colors

README Generator

Form-based README.md builder

Robots.txt Generator

Build robots.txt rules with a wizard

CSS Gradient Generator

Build linear and radial gradients visually

JSON Diff Tool

Compare two JSON objects structurally

Base64 Encoder Decoder

Encode or decode Base64 text instantly

URL Encoder Decoder

Percent-encode and decode URLs

Code Screenshot Maker

Turn code snippets into shareable images

Hex to Text Converter

Convert hex bytes to text and back

Git Command Cheat Sheet

Searchable reference for common Git commands

HTAccess Redirect Generator

Generate Apache .htaccess redirect rules

CSS Animation Generator

Build CSS keyframe animations with a live preview

SVG Path Editor

Preview and style SVG path data

Encode Quoted Printable

Encode or decode Quoted-Printable (MIME) text

Source Code Downloader

Plan a website source archive

Query String to JSON

Turn URL parameters into structured JSON

HTML Minifier

Compress HTML for production

HTML Formatter

Beautify messy HTML markup

UNIX Timestamp Converter

Timestamps to dates, with the unit detected

JavaScript Minifier

Shrink source code for distribution

Code Beautifier Multi-Language

Format code for easier reading

User Agent Parser

Inspect browser and device details

Text Encoding Detector

Identify likely text encodings

Crontab Guru Clone

Explain cron expressions in plain English

CSS Specificity Calculator

Cookie Viewer

ARIA Attribute Reference

GZIP Compression Test

Estimate GZIP compression ratio and savings

Unicode to Punycode

Browser Fingerprint Audit

Slug Generator

URL slugs that keep the letters others drop

JSON to TypeScript Types

Types that account for every array element, not just the first

Cron Expression Builder

Evaluates the schedule instead of just describing it

Code Syntax Highlighter

Highlighted HTML you can paste anywhere, even without CSS

String Escape Tool

Escape for twelve targets, and see why the context matters

Env File to JSON

Convert .env to JSON and back, respecting all three quote styles

JSON Validator

Find syntax errors with line-level hints

Tailwind Class Converter

CSS to utilities and back, with v4 values and nothing dropped

Color Code Converter

HEX, RGB, HSL, CMYK conversion

SVG Optimizer

Minify SVG code while keeping visuals

JavaScript Formatter

Pretty-print minified JS code

JSON Path Tester

Query JSON with JSONPath expressions

UUID Validator

Check UUID format and version

MIME Type Lookup

Find MIME types by file extension

Character Code Lookup

Get HTML codes for special characters

Chmod Calculator

Convert file permissions to octal notation

Flexbox Playground

Interactive flexbox property sandbox

CSS Units Converter

Convert px to rem, em and vw

HTML Entity Decode

Decode or encode HTML entities

Lua Beautifier

Format and indent messy Lua code

PHP Formatter & Beautifier

Format and indent messy PHP code

GraphQL Formatter

Format and indent GraphQL queries

SOAP Formatter

SOAP formatter — beautify SOAP XML envelopes free

XPath Tester

Test XPath expressions against XML

ASCII to Text

Convert ASCII codes back to readable text

Text to Octal

Convert text into octal character codes

Octal to Text

Convert octal codes back to readable text

Text to Decimal

Convert text into decimal character codes

Decimal to Text

Convert decimal codes back to readable text

Octal to Decimal

Convert base-8 numbers to base-10

Decimal to Octal

Convert base-10 numbers to base-8

HEX to Octal

Convert base-16 numbers to base-8

Octal to HEX

Convert base-8 numbers to base-16

HTML Table Generator

Build clean HTML table markup from rows and columns

Identifier Case Converter

Convert identifiers between naming conventions

GitHub Actions Workflow Builder

Draft a CI workflow YAML from your choices

Migration SQL Generator

Draft up and down migration SQL

IndexedDB Inspector

Inspect IndexedDB stores, records, and indexes

Focus Order Visualizer

See the keyboard tab order of a page

Binary File Diff

Compare two binary files byte by byte in hex

SQL Dump Splitter

Split large SQL dumps into loadable, statement-safe chunks

Raspberry Pi GPIO Pinout

Look up Pi header pins and their functions

Image Map Generator

Create clickable regions on an image

Regex Explainer

Break a regular expression into plain English

Vite Config Generator

Assemble a Vite config for your setup

Dockerfile Builder

Build a Dockerfile with sensible defaults

UUID Version Detector

Identify which UUID version you have

HAR File Viewer

Read a HAR capture without devtools

Notification Permission Tester

Test browser notification permission states

Bootstrap to Tailwind Converter

Map Bootstrap classes to Tailwind equivalents

Jupyter Notebook Viewer

View .ipynb cells and saved outputs online

Deep Link Builder

Deep link builder: intent URL, universal link, QR

BBCode Viewer

Preview BBCode as rendered HTML

JavaScript Syntax Validator

Find JavaScript syntax errors without running code

Mouse Button and Scroll Test

Test every mouse button and scroll wheel

Regex Generator from Examples

Infer a regex pattern from sample strings

tsconfig Builder

Generate a tsconfig.json from options

Makefile Generator

Generate a Makefile for your project

MongoDB ObjectId Decoder

Decode a MongoDB ObjectId's timestamp

Swagger to Postman Converter

Convert an OpenAPI spec to a Postman collection

Media Devices Lister

List connected cameras and microphones

Tailwind Config Generator

Generate a tailwind.config.js from options

Code Comment Stripper

Remove comments from source code

reStructuredText to Markdown

Convert RST documents to Markdown

Barcode Scanner

Scan barcodes with your camera

JSONL Dataset Formatter

Convert a JSON array to JSON Lines format

C# Escape / Unescape

Escape and unescape C# string literals

Base58 Encoder/Decoder

Encode and decode text using Base58

Byte to String Converter

Convert byte arrays to readable strings and back

DSA Helpers

Common data structure and algorithm utility snippets

Source Code Highlighter with HTML Export

Syntax-highlight code and export as styled HTML

GPU / WebGL Test

Check browser WebGL support and GPU capabilities

ESLint Config Builder

Build a custom .eslintrc through a form

GitLab CI Config Builder

Generate .gitlab-ci.yml pipelines visually

Retry & Backoff Calculator

Model retry delays for exponential backoff strategies

GraphQL Query Builder

Construct GraphQL queries with a visual builder

Geolocation API Tester

Test browser geolocation requests and responses

Screen Reader Text Preview

Preview how screen readers announce page content

Email Client Preview Tester

Preview email HTML across major clients

Stepper Steps per mm Calculator

Estimate travel resolution precisely

Keyboard Shortcut Conflict Checker

Find shortcut clashes fast

Unused CSS Finder

Spot selectors that never match

Structured Output Validator

Validate JSON-shaped responses

Firewall Rule Generator

Draft firewall rules quickly

Hex Editor

View and edit a file's raw bytes in hex and ASCII

Prompt Injection Test Suite

Run a checklist of common prompt-injection test strings

Sequence Diagram Generator

Turn simple text into a UML sequence diagram

gitattributes Generator

Generate a .gitattributes file for your project type

Babel Config Generator

Generate a babel.config.json for your project setup

.env Example Generator

Turn a real .env file into a safe .env.example

SQL Index Advisor

Get index suggestions from a SQL query and schema

Browser Storage Quota Checker

Check how much browser storage your site can use

ARIA Role Validator

Check ARIA roles and attributes in HTML for common mistakes

Critical CSS Extractor

Pull above-the-fold CSS rules out of a stylesheet

Fail2ban Config Generator

Generate a fail2ban jail.local configuration

Arduino Pin Reference

Look up pinout details for common Arduino boards

Coordinate Projection Tool

Convert between latitude/longitude and UTM coordinates

Engineering Incident Review

Retrospect technical incidents cleanly

API Contract Checker

OpenAPI diff tool: compare specs, catch breaking changes

JSON Schema Diff

Spot schema changes fast

Markdown Lint Auditor

Audit markdown style quickly

Git Commit Message Helper

Draft cleaner commit messages

Branch Name Normalizer

Format branch names consistently

Changelog Draft Maker

Turn changes into release notes

Release Readiness Checklist

Review launch steps before release

Dependency Update Planner

Plan package updates safely

Log File Summarizer

Condense logs into key events

Baud Rate Error Calculator

Check UART baud rate error percentage

Embedding Similarity Calculator

Compute cosine similarity between vector embeddings

PCB Impedance Calculator

Calculate microstrip trace impedance for PCB design

Rust Code Formatter

Beautify Rust source with rustfmt-style rules

Ansible Playbook Linter

Check YAML playbooks for common Ansible mistakes

Swift Codable Generator

Generate Swift Codable structs from JSON samples

Cron to Human Sentence

Explain a cron expression in plain English

Semantic Diff for Code

Compare two code snippets ignoring whitespace and comments

API Error Code Reference Builder

Build a searchable reference table of custom API error codes

Protobuf Schema Viewer

Protobuf schema viewer for field names, types & tags

gRPC Proto to JSON Sample

Generate a sample JSON payload from a proto message

cURL to Fetch Converter

Turn a curl command into JavaScript fetch code

Webhook Payload Inspector

Pretty-print and inspect a webhook JSON payload

Feature Toggle Naming Generator

Generate consistent feature flag names

Prettier Config Builder

Build a Prettier config visually

Jenkinsfile Generator

Draft a declarative pipeline

Rate Limit Planner

Model API request budgets

GraphQL to TypeScript Types

Sketch TypeScript from GraphQL

Endianness Converter

Swap byte order safely

Few-Shot Example Formatter

Format prompt examples consistently

Email CSS Inliner

Inline simple email CSS rules

Component Prop Table Generator

Generate clean component prop docs

JSON Config Merge Tool

Preview merged JSON configs

HTTP/2 vs HTTP/1.1 Explainer

Compare web protocol behavior

Feature Flag JSON Builder

Build a feature flag config JSON from a list of flags

REST Endpoint Namer

Generate consistent REST endpoint names from a resource and action

API Versioning Strategy Advisor

Get a recommended API versioning strategy for your context

Debounce/Throttle Visualizer

Visualize how debounce and throttle handle a burst of events

JSON Web Key Set Viewer

View a JWKS as a readable list of keys

Array Method Chain Visualizer

See an array's state after each method in a chain

Async/Await Flow Visualizer

See a timeline of sequential async/await execution