Client-side · No signup · No tracking

10 tools, free in your browser. Automate via API for $5/mo.

JSON, Base64, JWT, hashing, diffs, regex, cron, and more — use them free today. Subscribe to unlock the REST API for scripting and CI/CD.

▶ Watch Demo

Free · Always

Browser Tools

All 10 utilities run entirely in your browser. Nothing leaves your machine. No account needed.

JSON, Base64, Hashing, JWT, UUID
Timestamps, Regex, Diff, URL encode, Cron
No rate limits, no ads, no tracking

Pro · $5/month

REST API Access

Call any tool programmatically. Automate pipelines, scripts, and CI/CD workflows with a simple API key.

All 10 tools via POST /api/v1/*
Authenticate with X-Api-Key header
Unlimited requests, instant key delivery

Free

Browser Tools

{ }

JSON Formatter

Pretty-print, validate, and minify JSON

Base64 Encode/Decode

Convert text to and from Base64

Hash Generator

SHA-256, SHA-512, MD5 hashing

🔑

JWT Decoder

Decode and inspect JWT tokens

UUID Generator

Generate random v4 UUIDs

⏱

Timestamp Converter

Unix timestamps to ISO and back

Regex Tester

Test patterns, highlight matches

Diff Viewer

Compare two blocks of text

%20

URL Encoder/Decoder

Encode and decode URL components

⏰

Cron Parser

Show next run times for a cron expression

Markdown Preview

Render Markdown to HTML live

SQL

SQL Formatter

Beautify and format SQL queries

⇄

YAML ↔ JSON

Bidirectional YAML/JSON conversion

●

Color Converter

Convert HEX, RGB, HSL colors

Lorem Ipsum

Generate placeholder text

JSON Formatter

Paste your JSON

Base64 Encode/Decode

Input text

Hash Generator

Input text Algorithm

JWT Decoder

Paste JWT token

UUID Generator

Timestamp Converter

Input

Current time

Result

Regex Tester

Pattern Flags Test string

Diff Viewer

Original

Modified

URL Encoder/Decoder

Input

Cron Expression Parser

Cron expression (minute hour day month weekday) Number of next runs to show

Markdown Preview

Markdown Input

HTML Preview

SQL Formatter

SQL Query

YAML ↔ JSON Converter

Input (YAML or JSON)

Color Converter

Pick a color or enter a value below

HEX

RGB

HSL

Lorem Ipsum Generator

Paragraphs

Type

Pricing

Simple, transparent pricing

Free

All tools, forever free in your browser. No account required.

15 developer tools
Runs entirely in your browser
No signup, no tracking
No rate limits on browser use
REST API access
Programmatic automation
API key management

Pro

$5_/month

Full REST API access. Automate your workflows. API key delivered instantly.

Everything in Free
REST API for all 15 tools
Unlimited API requests
API key delivered instantly
Use in CI/CD, scripts, bots
Simple X-Api-Key auth

Already subscribed? Manage billing:

Pro API

API Reference

tools available via REST API

1 header

X-Api-Key: atpro_... — that's all you need

Browser tools are always free. For programmatic access, use /api/v1/* with your X-Api-Key header. Requires a Pro subscription.

Verify your API key

curl https://apitoolkit.pro/api/verify-key \
  -H "X-Api-Key: atpro_..."

Format JSON

curl -X POST https://apitoolkit.pro/api/v1/format-json \
  -H "X-Api-Key: atpro_..." \
  -H "Content-Type: application/json" \
  -d '{"key":"value","nested":{"a":1}}'

All endpoints

# Base64
curl -X POST https://apitoolkit.pro/api/v1/base64 \
  -H "X-Api-Key: atpro_..." \
  -d '{"action":"encode","input":"hello"}'

# Hash
curl -X POST https://apitoolkit.pro/api/v1/hash \
  -H "X-Api-Key: atpro_..." \
  -d '{"input":"hello","algorithm":"sha256"}'

# JWT decode
curl -X POST https://apitoolkit.pro/api/v1/jwt-decode \
  -H "X-Api-Key: atpro_..." \
  -d '{"token":"eyJ..."}'

# UUID
curl -X POST https://apitoolkit.pro/api/v1/uuid \
  -H "X-Api-Key: atpro_..."

# Timestamp
curl -X POST https://apitoolkit.pro/api/v1/timestamp \
  -H "X-Api-Key: atpro_..." \
  -d '{"action":"to_iso","input":"1712345678"}'

# Regex
curl -X POST https://apitoolkit.pro/api/v1/regex \
  -H "X-Api-Key: atpro_..." \
  -d '{"pattern":"\\w+","flags":"g","input":"hello world"}'

# Diff
curl -X POST https://apitoolkit.pro/api/v1/diff \
  -H "X-Api-Key: atpro_..." \
  -d '{"a":"line1\nline2","b":"line1\nline3"}'

# URL encode
curl -X POST https://apitoolkit.pro/api/v1/url-encode \
  -H "X-Api-Key: atpro_..." \
  -d '{"action":"encode","input":"hello world"}'

# Cron parser
curl -X POST https://apitoolkit.pro/api/v1/cron \
  -H "X-Api-Key: atpro_..." \
  -d '{"expression":"*/5 * * * *","count":5}'

# Markdown to HTML
curl -X POST https://apitoolkit.pro/api/v1/markdown \
  -H "X-Api-Key: atpro_..." \
  -d '{"input":"# Hello\n\nThis is **bold**."}'

# SQL formatter
curl -X POST https://apitoolkit.pro/api/v1/sql-formatter \
  -H "X-Api-Key: atpro_..." \
  -d '{"input":"SELECT id,name FROM users WHERE active=1","action":"format"}'

# YAML to JSON
curl -X POST https://apitoolkit.pro/api/v1/yaml-json \
  -H "X-Api-Key: atpro_..." \
  -d '{"input":"name: John\nage: 30","action":"yaml_to_json"}'

# Color converter
curl -X POST https://apitoolkit.pro/api/v1/color \
  -H "X-Api-Key: atpro_..." \
  -d '{"input":"#6366f1","from":"hex"}'

# Lorem ipsum generator
curl -X POST https://apitoolkit.pro/api/v1/lorem-ipsum \
  -H "X-Api-Key: atpro_..." \
  -d '{"paragraphs":3}'

10 tools, free in your browser. Automate via API for $5/mo.

Browser Tools

REST API Access

JSON Formatter

Base64 Encode/Decode

Hash Generator

JWT Decoder

UUID Generator

Timestamp Converter

Regex Tester

Diff Viewer

URL Encoder/Decoder

Cron Parser

Markdown Preview

SQL Formatter

YAML ↔ JSON

Color Converter

Lorem Ipsum

JSON Formatter

Base64 Encode/Decode

Hash Generator

JWT Decoder

UUID Generator

Timestamp Converter

Regex Tester

Diff Viewer

URL Encoder/Decoder

Cron Expression Parser

Markdown Preview

SQL Formatter

YAML ↔ JSON Converter

Color Converter

Lorem Ipsum Generator

More Developer Tools

Get developer tips in your inbox