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Tool Categories

Browse tools by category — find exactly what you need

Encoding

11 tools

Base64 Converter

Encode/decode Base64

URL Encode/Decode

URL encode/decode text

HTML Entities

HTML entity encode/decode
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Unicode Converter

Encode/decode Unicode escape sequences

Hex Converter

Encode/decode text to/from hex
01 10 11 02 A1 FF

Binary Converter

Convert text to/from binary
01 10 11 02 A1 FF

ASCII Converter

Convert text to/from ASCII codes
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UTF-8 Converter

Encode/decode UTF-8 byte sequences
A a

ROT13 Cipher

Encode/decode with ROT13 cipher
\\ \"

Shell Escape

Escape strings for bash, shell and command line
\\ \"

Morse Code

Convert text to/from Morse code

Generators

7 tools

UUID Generator

Generate UUID v4

QR Code Generator

Generate QR codes

Lorem Ipsum

Generate placeholder text

Password Generator

Create secure passwords

Nano ID Generator

Generate compact unique IDs
A a

Slug Generator

Create URL-friendly slugs
a7 K3 m9 X2

Random String Generator

Generate random alphanumeric strings

Colors & Design

10 tools

Color Picker

HEX/RGB/HSL converter

CSS Gradient

Create gradient CSS

Color Contrast Checker

Check WCAG contrast ratios

Color Palette Generator

Generate harmonious color palettes

Flexbox Generator

Visual CSS flexbox layout generator

CSS Grid Generator

Visual CSS grid layout generator

Box Shadow Generator

Generate CSS box-shadow styles visually

Border Radius Generator

Generate CSS border-radius styles visually

Color Converter

Convert colors between HEX, RGB, HSL and CMYK

Tailwind Color Generator

Generate Tailwind CSS color palette configs

Data Converters

18 tools

JSON Formatter

Format, validate, minify JSON

JSON Schema Generator

Generate JSON Schema from JSON data

JSON to Code

Convert JSON to TypeScript, Go, Rust, Kotlin, Dart

Mock Data Generator

Generate fake JSON data, mocks and fixtures

Timestamp Converter

Unix timestamp converter

Hash Generator

MD5, SHA-1, SHA-256, SHA-512
01 10 11 02 A1 FF

Number Base

Dec/Hex/Bin/Oct converter

Timezone Converter

Convert time between different timezones

JSON ↔ YAML

Convert JSON/YAML

CSV to JSON

Convert CSV data to JSON

JSON Compare

Compare and diff two JSON objects
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JSON Escape

Escape/unescape JSON strings

JSON Sort

Sort JSON object keys alphabetically

JSON to CSV

Convert JSON array to CSV format

JSON Flatten

Flatten nested JSON to dot-notation keys

JSON ↔ XML

Convert between JSON and XML formats

JSON to TOML

Convert JSON to TOML config format

JSON Tree Viewer

Visualize JSON structure as a tree

Development

17 tools

HTML Preview

Preview HTML code in real-time
01 10 11 02 A1 FF

chmod Calculator

Calculate Unix file permissions and chmod values

LLM Token Counter

Count tokens for OpenAI, Claude and Gemini models

Prompt Tools

Format and optimize LLM prompts for better results

JWT Decoder

Decode JSON Web Tokens

JWT Encoder

Create and sign JSON Web Tokens

JWT Inspector

Inspect JWT claims, expiry, and structure

Regex Tester

Test regular expressions

Diff Checker

Compare text differences

SQL Formatter

Format SQL queries

SQL Validator

Validate SQL syntax and find errors

URL Parser

Parse URL components

HTTP Status Codes

HTTP status code reference

Cron Expression Parser

Parse cron schedule expressions

Cron Expression Generator

Build cron schedule expressions visually

Regex Cheat Sheet

Quick reference for regex syntax and patterns

Regex Generator

Generate regex patterns from plain text descriptions

Text Tools

11 tools
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String Escaper

Escape/unescape strings
A a

Text Case

UPPER/lower/CamelCase

Word Counter

Count words, chars, lines

Dedupe Lines

Remove duplicate lines

Character Counter

Count characters, letters, digits and spaces

Line Counter

Count total, empty and non-empty lines

Remove Empty Lines

Remove blank and whitespace-only lines

Sort Lines

Sort text lines alphabetically A-Z or Z-A

Shuffle Lines

Randomly shuffle and reorder text lines

Reverse Text

Reverse characters, words or line order

Markdown Previewer

Preview Markdown in real-time

Network

10 tools

IP Address Lookup

Lookup IP geolocation & ISP
01 10 11 02 A1 FF

My IP Address

Show your public IP address

DNS Lookup

Query DNS records

DNS Log Monitor

Real-time DNS query logging via dig.pm
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User Agent Parser

Parse browser user agent

Query String Parser

Parse and decode URL query parameters

HTTP Header Viewer

View and analyze HTTP request/response headers

WHOIS Lookup

Lookup domain registration and ownership info
12ms

Ping Tool

Test network latency and packet loss
:80 :443

Port Checker

Check if TCP ports are open or closed

Image Tools

11 tools

Image to Base64

Convert image to Base64 data URI

Base64 Image Viewer

Decode and view Base64-encoded images

SVG Viewer

View and preview SVG code in real-time

SVG Optimizer

Optimize and clean up SVG markup

SVG Minifier

Minify and compress SVG code

Image Compressor

Compress JPEG, PNG and WebP images

Image Crop

Crop and trim images in the browser

Image Resize

Resize images to exact dimensions

Favicon Generator

Generate favicon.ico from any image

Image Format Converter

Convert images between PNG, JPEG, WebP, SVG

EXIF Viewer

View EXIF metadata from JPEG photos

Security

7 tools

SSL Certificate Checker

Check SSL certificate details

Password Strength Meter

Evaluate password strength

CRC32 Hash

Generate CRC32 checksum from text

Bcrypt Hash Generator

Hash passwords with bcrypt algorithm

AES Encrypt/Decrypt

Encrypt and decrypt text with AES-256/192/128-GCM

RSA Key Generator

Generate RSA public/private key pairs

HMAC Generator

Generate HMAC with SHA-256 and SHA-512

Formatters

6 tools

SQL Minifier

Minify and compress SQL queries

CSS Formatter

Format & beautify CSS

CSS Minifier

Minify and compress CSS code

HTML Formatter

Format & beautify HTML

HTML Minifier

Minify and compress HTML code

JavaScript Formatter

Format & beautify JavaScript

Calculators

1 tools
01 10 11 02 A1 FF

PX to REM Converter

Convert PX to REM/EM units

SEO Tools

2 tools
#1 #2 #3

Robots.txt Validator

Validate and test robots.txt rules for URLs
#1 #2 #3

Sitemap Validator

Validate XML sitemap structure and format

Why Choose Us?

The tools you need, designed the way you want them

100% Private

All processing happens locally in your browser. Your data never leaves your computer.

Lightning Fast

No server roundtrips. No loading spinners. Just instant results every time.

Always Free

No sign ups. No paywalls. No limits. Just tools that work for developers.

Developer Guides

In-depth tutorials to help you get the most out of our tools

JSON Data Debugging Guide

A systematic approach to finding and fixing JSON errors. Covers validation, formatting, JWT debugging, and real-world API workflows.

Web Encoding Explained

Base64, URL encoding, and HTML entities — when to use each, common mistakes, and practical code examples.

Text Processing for Developers

Regex patterns, case conversion, deduplication, and word counting — practical workflows for everyday text tasks.

Latest Articles

In-depth guides and tutorials for developers

Security

Password Security & Hash Algorithms

MD5 vs SHA-256, password hashing best practices, UUIDs, and how to avoid common security mistakes.
Frontend

CSS Colors & Gradients Guide

HEX, RGB, HSL explained. Building color palettes and creating beautiful CSS gradients with practical examples.

Frequently Asked Questions

Got questions? We've got answers.

Are these tools really free?

Yes! All tools are 100% free to use, with no hidden fees, no paywalls, and no sign-up required. We believe essential developer tools should be accessible to everyone.

Is my data safe? Where is it processed?

All processing happens entirely in your browser. Your data never leaves your computer — we don't upload, store, or even see anything you paste into our tools. This also means the tools work offline once the page is loaded.

Do I need to create an account?

Nope! No accounts, no registrations, no email verification. Just open the tool you need and start using it immediately. We hate unnecessary sign-ups as much as you do.

Are there any usage limits?

No limits at all. Use any tool as many times as you want, with any amount of data your browser can handle. Since everything runs locally, the only limit is your computer's performance.

Can I suggest a new tool or feature?

Absolutely! We love hearing from the developer community. You can reach out through our GitHub repository to suggest new tools, report bugs, or even contribute code.

Does this site work on mobile?

Yes! DevTools Hub is fully responsive and works great on desktops, tablets, and mobile phones. All tools are designed with a mobile-first approach so you can be productive on any device.

Ready to get started?

Pick a tool from our collections and start being more productive today

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