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Developer Tools

Explore 51 free Developer tools for JSON, XML, HTML, encoding, hashing, regex, code formatting and browser utilities. The collection is organized for developers, testers and technical learners and focuses on inspecting, transforming and validating technical data.

What you can do with Developer tools

Developers, testers and technical learners can use these tools from their dedicated pages. Each tool includes its purpose, instructions, result guidance and links to closely related utilities.

Choose a tool by name or filter the category. For calculations, verify units and assumptions before relying on the result. For text, document, web and diagnostic tools, review generated output before using it in production, publication or formal decisions.

51 free toolsDedicated pagesMobile friendlyNo registration required
Browse by level
Levels are discovery guides, not formal academic classifications.

Calculators & Analysis

1 tools
DeveloperIntermediate

.htaccess Builder

Generate common Apache rewrite, redirect, caching and security directives.

New · usage tracking activeOpen tool →

Checks & Diagnostics

8 tools
DeveloperIntermediate

API Tester

Send GET, POST, PUT, PATCH or DELETE requests to CORS-enabled APIs and inspect responses.

New · usage tracking activeOpen tool →
DeveloperIntermediate

CORS Tester

Test whether a public endpoint permits browser cross-origin requests.

New · usage tracking activeOpen tool →
DeveloperIntermediate

CSS Selector Extractor

Extract CSS selector blocks from pasted CSS for audit and cleanup.

New · usage tracking activeOpen tool →
DeveloperAdvanced

JSON Schema Validator

Check JSON data against common JSON Schema required fields and primitive types.

New · usage tracking activeOpen tool →
DeveloperAdvanced

Regex Tester

Use Regex Tester for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

Text Difference Checker

Use Text Difference Checker for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

Webhook Tester

Send test webhook payloads to a public endpoint and inspect the response.

New · usage tracking activeOpen tool →
DeveloperIntermediate

YAML Validator

Check common YAML indentation and key-value structure issues.

New · usage tracking activeOpen tool →

Converters & Formatters

22 tools
DeveloperIntermediate

Base32 Encoder / Decoder

Use Base32 Encoder / Decoder for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

Base64 Encoder / Decoder

Use Base64 Encoder / Decoder for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

HEX / RGB Color Converter

Use HEX / RGB Color Converter for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

CSS Minifier

Use CSS Minifier for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

Hex ↔ Text Converter

Use Hex ↔ Text Converter for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

HTML Entity Encoder / Decoder

Use HTML Entity Encoder / Decoder for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

HTML Formatter / Beautifier

Use HTML Formatter / Beautifier for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

HTML Minifier

Use HTML Minifier for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

JavaScript Minifier

Use JavaScript Minifier for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

JSON Formatter & Validator

Use JSON Formatter & Validator for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

JSON Minifier

Use JSON Minifier for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperAdvanced

JWT Decoder

Use JWT Decoder for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

Markdown / HTML Converter

Convert common Markdown syntax to HTML and basic HTML back to Markdown.

New · usage tracking activeOpen tool →
DeveloperIntermediate

Number Base Converter

Convert integers between binary, octal, decimal and hexadecimal bases.

New · usage tracking activeOpen tool →
DeveloperIntermediate

SQL Formatter

Format common SQL statements for easier reading.

New · usage tracking activeOpen tool →
DeveloperBasic

Unix Timestamp Converter

Use Unix Timestamp Converter for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

TOML Converter

Convert simple TOML key-value data to JSON and JSON objects to TOML.

New · usage tracking activeOpen tool →
DeveloperIntermediate

Universal Data Format Converter

Convert JSON, XML, YAML, CSV, TSV, INI, TOML and Properties-style data.

New · usage tracking activeOpen tool →
DeveloperIntermediate

URL Encoder / Decoder

Use URL Encoder / Decoder for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

UTF-8 Encoder / Decoder

Use UTF-8 Encoder / Decoder for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

XML Formatter

Use XML Formatter for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

XML Minifier

Use XML Minifier for common developer and technical tasks.

New · usage tracking activeOpen tool →

Data & Reference

4 tools
DeveloperBasic

Browser Storage Viewer & Cleaner

Inspect and clear localStorage and sessionStorage for this website.

New · usage tracking activeOpen tool →
DeveloperIntermediate

HTML Viewer & Preview

Use HTML Viewer & Preview for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

Query String Parser

Use Query String Parser for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperAdvanced

Regex Pattern Dictionary

Browse practical regular-expression patterns with examples.

New · usage tracking activeOpen tool →

General Utilities

10 tools
DeveloperIntermediate

Cron Expression Helper

Use Cron Expression Helper for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

CSV to JSON

Use CSV to JSON for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperBasic

Hex Editor

Inspect small local files as hexadecimal and ASCII without uploading them to permanent storage.

New · usage tracking activeOpen tool →
DeveloperIntermediate

HTML Editor

Edit HTML with a live browser preview.

New · usage tracking activeOpen tool →
DeveloperIntermediate

HTML Tag Stripper

Use HTML Tag Stripper for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

JSON to CSV

Use JSON to CSV for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

JSON to XML

Use JSON to XML for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

JSON to YAML

Use JSON to YAML for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

Markdown Preview

Use Markdown Preview for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

XML to JSON

Use XML to JSON for common developer and technical tasks.

New · usage tracking activeOpen tool →

Generators & Builders

4 tools
DeveloperIntermediate

API Request Builder

Build a cURL request from method, URL, headers and request body.

New · usage tracking activeOpen tool →
DeveloperAdvanced

Hash Generator

Use Hash Generator for common developer and technical tasks.

New · usage tracking activeOpen tool →
DeveloperIntermediate

URL Slug Generator

Use URL Slug Generator for common developer and technical tasks.

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DeveloperIntermediate

UUID Generator

Use UUID Generator for common developer and technical tasks.

New · usage tracking activeOpen tool →

Writing & Content

2 tools
DeveloperAdvanced

Technical Cheat Sheet Hub

Quick-reference snippets for HTTP, Git, Linux, regex, SQL and web development.

New · usage tracking activeOpen tool →
DeveloperIntermediate

HTML to Text

Use HTML to Text for common developer and technical tasks.

New · usage tracking activeOpen tool →