Developer Tools

Free Developer Tools

Format JSON, convert CSV, encode URLs, decode Base64, inspect JWTs, escape HTML entities, and convert number bases. These utilities run the transform step in your browser for quick debugging.

Featured

Tools with full guides

These pages include comparison tables, FAQs, and longer walkthroughs. Use them when you need more than a quick convert.

JSON Formatter

Validate, pretty-print, minify, and inspect JSON data in your browser.

Open guide

Base64 Encoder / Decoder

Encode text to Base64 or decode Base64 back into readable text.

Open guide

CSV to JSON

Convert spreadsheet-style CSV rows into structured JSON objects.

Open guide

JWT Decoder

Inspect JWT headers and payloads without sending tokens to a server.

Open guide

More tools in this category

Focused converters and helpers for specific formats or calculations.

URL Encoder / Decoder

Percent-encode text for URLs or decode copied URL values.

Open tool

JSON to CSV

Convert JSON arrays into CSV for spreadsheets, exports, and reports.

Open tool

HTML Entities

Encode special characters for HTML or decode entity text back to readable characters.

Open tool

Number Base Converter

Convert between binary, octal, decimal, and hexadecimal numbers.

Open tool

Use cases

When these tools help

Inspect copied API payloads, logs, tokens, and encoded values.
Move data between spreadsheet, JSON, URL, and text formats.
Debug small snippets without setting up a local script or sharing data with a third-party account.

Why browser-based developer utilities are useful

Small formatting and encoding tasks interrupt real work. A focused browser tool is often faster than opening an IDE, writing a one-off script, or pasting into a large SaaS product. The key is to understand what the transformation does and what it does not prove.

Formatting JSON does not validate business rules, Base64 is not encryption, and decoding a JWT does not verify its signature. Use these tools to inspect shape and syntax quickly, then rely on your application, tests, and security process for deeper validation.

For CSV and JSON, use the direction switcher on the tool page and test a small sample before converting large exports. See the blog article on CSV and JSON round trips for common pitfalls.

Epoch timestamps live under Time tools (Unix Timestamp converter). Developer utilities here focus on text shape, encoding, and token inspection.

All tools Start with JSON Formatter