Free & Open Source

Developer Tools
Made Simple

A curated collection of free online developer tools. Format JSON, encode Base64, test regex, and more — all in your browser.

Tools

API Calls

100%

Free

All Tools

25 available

Encoding & Encryption

Base64

Encode and decode text or files to and from Base64 format instantly

base64encodedecode

URL Encoder

Encode and decode URLs, query parameters, and special characters

urlencodedecode

Hash Generator

Generate MD5, SHA-1, SHA-256, and SHA-512 hashes from any text input

hashmd5sha

HTML Entity Encoder

Encode and decode HTML entities to safely display special characters in HTML

htmlentityencode

JWT Decoder

Decode JWT tokens to inspect header, payload, and signature without verification

jwttokendecode

Format & Convert

JSON Formatter

Format, validate, and beautify JSON data with syntax highlighting and error detection

jsonformatbeautify

Timestamp Converter

Convert between Unix timestamps and human-readable dates in multiple formats

timestampunixepoch

Color Converter

Convert colors between HEX, RGB, and HSL formats with live preview

colorhexrgb

Case Converter

Convert text between uppercase, lowercase, title case, camelCase, and more

caseuppercaselowercase

JSON ⇄ YAML

Convert between JSON and YAML formats with syntax validation

jsonyamlconvert

SQL Formatter

Format and beautify SQL queries with proper indentation and capitalization

sqlformatbeautify

Generators

UUID Generator

Generate UUID v1 and v4 identifiers, with bulk generation and copy support

uuidguididentifier

QR Code Generator

Generate QR codes from text, URLs, or any data with customizable size

qrcodebarcode

Lorem Ipsum Generator

Generate Lorem Ipsum placeholder text with customizable paragraphs, words, or bytes

loremipsumplaceholder

Password Generator

Generate strong, secure passwords with customizable length and character sets

passwordgeneratorsecure

Text Tools

Regex Tester

Test and debug regular expressions with real-time matching and explanations

regexregular expressionpattern

Text Diff Checker

Compare two texts side by side and find the differences instantly

diffcomparetext

Markdown Preview

Write Markdown and preview the rendered HTML in real time

markdownpreviewmd

Text Counter

Count words, characters, sentences, paragraphs, and estimate reading time

textcountwords

Network & System

Number Base Converter

Convert numbers between binary, octal, decimal, and hexadecimal bases instantly

binaryoctaldecimal

Cron Expression Parser

Parse cron expressions and see their meaning in plain English

cronscheduleexpression

IP Lookup

Look up detailed information about any IP address including location and ISP

iplookupgeo

User Agent Parser

Parse and decode User-Agent strings to identify browsers, OS, and devices

useragentbrowser

HTTP Status Codes

A complete reference of HTTP status codes with descriptions — 1xx through 5xx

httpstatuscode

Unix Permissions Calculator

Convert between octal (chmod) and symbolic Unix file permissions

unixpermissionschmod

Why DevTools?

Lightning Fast

All processing happens in your browser. No server roundtrips, no waiting.

Always Available

Works offline once loaded. No API keys, no rate limits, no restrictions.

Developer First

Built by developers, for developers. Every tool is designed for real workflows.

Developer ToolsMade Simple