Free browser-based tools

Fast browser-based utilities for developers, API work, debugging, and daily engineering tasks.

Built for developers, API testers, technical writers, and support engineers. No account is required, and common calculations or transformations run locally in the browser.

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Each page includes an interactive tool, practical example, notes, and related tools.

JSON Formatter and Validator

Format, minify, validate, and inspect JSON payloads. JSON and Data

JSON to CSV Converter

Convert arrays of JSON objects into CSV for spreadsheets and reports. Debugging

Regex Tester

Test regular expressions against sample text and inspect matches. Web Utilities

Timestamp Converter

Convert Unix timestamps and ISO dates across common formats. Encoding

Base64 Encoder and Decoder

Encode and decode Base64 text in the browser. Encoding

URL Encoder and Decoder

Encode and decode URL components and query strings. Debugging

JWT Decoder

Decode JWT header and payload locally without verifying signatures. Web Utilities

UUID Generator

Generate UUID v4 values for testing, fixtures, and identifiers. Encoding

Hash Generator

Generate SHA-256 hashes from text using the browser Web Crypto API. Web Utilities

Query String Parser

Parse query strings into readable key-value pairs. Encoding

HTML Entity Encoder

Escape and unescape common HTML entities. JSON and Data

API Payload Formatter

Clean, format, and inspect API request or response payloads. JSON and Data

JSON Minifier

Minify formatted JSON into compact payload text. JSON and Data

JSON Validator

Validate JSON and show parse errors before using API data. JSON and Data

API Response Prettifier

Format API JSON responses for debugging and documentation. Web Utilities

Query Parameter Decoder

Decode and inspect URL query parameters from copied links. Encoding

URL Component Encoder

Encode URL components for links, redirects, and API requests. Debugging

JWT Payload Viewer

Inspect JWT header and payload fields locally in the browser. Encoding

SHA-256 Text Hash

Generate SHA-256 hashes for text snippets and examples. Web Utilities

UUID Batch Generator

Generate batches of UUID v4 values for fixtures and tests. Web Utilities

Epoch Time Converter

Convert epoch timestamps for logs, databases, and APIs. Encoding

HTML Escape Tool

Escape HTML snippets for safe display in examples. Encoding

Base64 Decoder

Decode Base64 strings for safe inspection and debugging. Debugging

Regex Match Counter

Count regex matches and inspect matched text.

JSON and Data

JSON and Data

Focused tools for common developer tools workflows.

JSON Formatter and Validator

Format, minify, validate, and inspect JSON payloads. JSON and Data

JSON to CSV Converter

Convert arrays of JSON objects into CSV for spreadsheets and reports. JSON and Data

API Payload Formatter

Clean, format, and inspect API request or response payloads. JSON and Data

JSON Minifier

Minify formatted JSON into compact payload text. JSON and Data

JSON Validator

Validate JSON and show parse errors before using API data. JSON and Data

API Response Prettifier

Format API JSON responses for debugging and documentation.

Encoding

Encoding

Focused tools for common developer tools workflows.

Base64 Encoder and Decoder

Encode and decode Base64 text in the browser. Encoding

URL Encoder and Decoder

Encode and decode URL components and query strings. Encoding

Hash Generator

Generate SHA-256 hashes from text using the browser Web Crypto API. Encoding

HTML Entity Encoder

Escape and unescape common HTML entities. Encoding

URL Component Encoder

Encode URL components for links, redirects, and API requests. Encoding

SHA-256 Text Hash

Generate SHA-256 hashes for text snippets and examples. Encoding

HTML Escape Tool

Escape HTML snippets for safe display in examples. Encoding

Base64 Decoder

Decode Base64 strings for safe inspection and debugging.

Web Utilities

Web Utilities

Focused tools for common developer tools workflows.

Timestamp Converter

Convert Unix timestamps and ISO dates across common formats. Web Utilities

UUID Generator

Generate UUID v4 values for testing, fixtures, and identifiers. Web Utilities

Query String Parser

Parse query strings into readable key-value pairs. Web Utilities

Query Parameter Decoder

Decode and inspect URL query parameters from copied links. Web Utilities

UUID Batch Generator

Generate batches of UUID v4 values for fixtures and tests. Web Utilities

Epoch Time Converter

Convert epoch timestamps for logs, databases, and APIs.

Debugging

Debugging

Focused tools for common developer tools workflows.

Regex Tester

Test regular expressions against sample text and inspect matches. Debugging

JWT Decoder

Decode JWT header and payload locally without verifying signatures. Debugging

JWT Payload Viewer

Inspect JWT header and payload fields locally in the browser. Debugging

Regex Match Counter

Count regex matches and inspect matched text.

Guides

How to use these tools well

Short guides that explain workflows, mistakes, and practical use cases.

A practical workflow for using developer tools

How to combine multiple developer tools for faster work. Guide

Quality checks for developer tools

Review inputs, outputs, and edge cases before using results. Guide

Why browser-based tools are useful

Privacy, speed, and practical limitations of client-side tools. Guide

Developer Tools checklist

A simple checklist for choosing the right tool for the job.