26 Free Developer Tools — No Signup, No Tracking, Just Use Them

Why We Built These

Most "free" developer tool sites are ad farms. You search for a Base64 decoder, land on a page with 14 ads, and hope your JWT token isn't being logged somewhere.

We built these tools with a simple rule: everything runs in your browser. Your data doesn't hit a server. There's no tracking pixel watching what you paste. There's no signup wall after your third use.

Here's what's available right now.

Encoders & Decoders

Tools for encoding, decoding, and inspecting data formats.

Base64 Encoder/Decoder — Encode text to Base64 or decode Base64 back to text. Supports URL-safe encoding (replaces + and / with - and _).

URL Encoder/Decoder — Encode and decode URL components or full URLs. Useful when debugging query strings or building API requests with special characters.

JWT Decoder — Paste a JSON Web Token and see the decoded header, payload, and signature. Automatically converts iat, exp, and nbf timestamps to human-readable dates so you can instantly see when a token expires.

HTML Entity Encoder — Encode special characters (<, >, &, ") to HTML entities, or decode entities back to characters. Has an "encode all" mode for full numeric entity encoding.

Unicode Converter — Convert between text and Unicode escape sequences in JavaScript (\u0048), HTML (H), or CSS (\48) formats. Works both directions.

Text Utilities

Tools for analyzing and transforming text.

Word Counter — Paste any text and get word count, character count (with and without spaces), sentence count, paragraph count, average word length, and estimated reading time. Useful for essays, articles, and social media posts.

Case Converter — Convert text between UPPERCASE, lowercase, Title Case, Sentence case, camelCase, PascalCase, snake_case, kebab-case, and CONSTANT_CASE. Particularly useful when converting between naming conventions in code.

Find & Replace — Search and replace text with optional regex support. Toggle case sensitivity and choose between replacing the first match or all occurrences.

Line Sorter — Sort lines alphabetically, numerically, or by length. Ascending, descending, or random shuffle. Options to ignore case and trim whitespace.

Remove Duplicates — Remove duplicate lines from text. Choose whether to ignore case, trim whitespace, and preserve original order. Great for cleaning up lists.

Generators

Tools that create things — no input needed, just configure and generate.

UUID Generator — Generate UUIDs in v4 (random), v1 (timestamp-based), or v7 (timestamp + random, sortable). Bulk generate up to 100 at once, with options for uppercase and dash removal.

Password Generator — Generate cryptographically secure random passwords using crypto.getRandomValues(). Configure length (4-128), character types, and exclude ambiguous characters like 0/O and l/1.

Lorem Ipsum Generator — Generate placeholder text as paragraphs, sentences, or words. Optionally start with the classic "Lorem ipsum dolor sit amet..." opening.

Hash Generator — Generate MD5, SHA-1, SHA-256, and SHA-512 hashes of any text. All SHA hashes use the Web Crypto API. Compute all algorithms at once or pick a specific one.

Slug Generator — Convert any text to a URL-friendly slug. Handles Unicode characters, configurable separator (hyphen or underscore), optional max length.

Developer Utilities

Reference tools and converters for common dev tasks.

Cron Expression Parser — Paste a cron expression and get a plain-English explanation of the schedule, a breakdown of each field, and the next N scheduled runs. Supports standard 5-field, 6-field (with seconds), and 7-field (with year) formats.

Timestamp Converter — Convert between Unix timestamps and human-readable dates. Auto-detects seconds vs milliseconds. Shows ISO 8601, local time, UTC, and relative time ("3 days ago"). Works both ways — paste a timestamp or a date string.

JSONPath Tester — Test JSONPath expressions against JSON data. Supports dot notation, bracket notation, wildcards, and array indexing. Paste your JSON, write a query, and see the result.

HTTP Status Codes — Quick reference for HTTP status codes. Search by code number (404), status name ("not found"), or category ("client error"). Shows the description and category for each match.

MIME Type Lookup — Look up MIME types by file extension (.json → application/json) or by MIME type (image/png → .png). Covers 50+ common file types across documents, images, audio, video, fonts, and archives.

Data Converters

Convert between data formats in one click. Every converter runs in your browser — your data never leaves your device, which matters when you're converting config files with database URLs or API keys.

CSV to JSON

Open CSV to JSON Converter

Paste CSV data or upload a .csv file and get a formatted JSON array of objects.

• Headers as object keys (toggle off for raw arrays)
• Quoted fields with commas inside them ("Smith, John" stays as one field)
• Custom delimiters — comma, semicolon, tab, or pipe
• Empty cells converted to empty strings, not dropped

Example input:

name,email,role
Sara,sara@example.com,Designer
Omar,omar@example.com,Developer

Output:

[
  { "name": "Sara", "email": "sara@example.com", "role": "Designer" },
  { "name": "Omar", "email": "omar@example.com", "role": "Developer" }
]

JSON to CSV

Open JSON to CSV Converter

Convert a JSON array of objects to CSV. Automatically extracts all unique keys across all objects as column headers, so objects don't need identical keys. Handles values containing commas, quotes, and newlines by properly escaping them.

When you need this:

• Exporting API response data to a spreadsheet
• Creating CSV downloads from JSON data
• Preparing data for import into tools that only accept CSV

JSON to YAML

Open JSON to YAML Converter

Paste JSON and get clean YAML output with 2-space indentation.

When you need this:

• Converting package.json style configs to YAML format
• Creating Kubernetes manifests, Docker Compose files, or CI/CD configs from JSON data
• Switching between config formats when a tool requires YAML instead of JSON

Example:

{
  "server": {
    "port": 3000,
    "host": "0.0.0.0"
  },
  "database": {
    "url": "postgresql://localhost:5432/mydb"
  }
}

Becomes:

server:
  port: 3000
  host: 0.0.0.0
database:
  url: postgresql://localhost:5432/mydb

YAML to JSON

Open YAML to JSON Converter

Convert YAML to formatted JSON with your choice of 2-space or 4-space indentation. Handles nested objects, arrays, multi-line strings, and comments (stripped in JSON output since JSON doesn't support them).

When you need this:

• Debugging YAML configuration files (JSON is easier to validate)
• Feeding YAML config data into JavaScript applications
• Converting CI/CD pipeline configs to JSON for programmatic manipulation

XML to JSON

Open XML to JSON Converter

Convert XML documents to JSON. Preserves attributes (as @attributeName), text content (as #text), and automatically groups repeated elements into arrays.

Example:

<catalog>
  <book id="1">
    <title>The Pragmatic Programmer</title>
    <price>49.99</price>
  </book>
  <book id="2">
    <title>Clean Code</title>
    <price>39.99</price>
  </book>
</catalog>

The two <book> elements are automatically grouped into an array — no configuration needed.

JSON to XML

Open JSON to XML Converter

Convert JSON to well-formed XML with proper indentation and entity escaping. Handles nested objects, arrays (each item wrapped in the parent key's tag), and special characters.

When you need this:

• Integrating with legacy SOAP APIs that require XML
• Generating XML feeds or sitemaps from JSON data
• Creating XML configuration files from structured data

Markdown to HTML

Open Markdown to HTML Converter

Convert Markdown to HTML with support for headings, bold, italic, links, images, code blocks, lists, blockquotes, and horizontal rules. Option to wrap in a full HTML document with <!DOCTYPE html>, <head>, and <body> tags.

When you need this:

• Converting README files to HTML for documentation sites
• Previewing Markdown content as rendered HTML
• Generating HTML email content from Markdown drafts

TSV to JSON

Open TSV to JSON Converter

Convert tab-separated values to JSON. Useful for data copied from spreadsheets — Google Sheets and Excel copy as TSV by default, so you can select cells, Ctrl+C, and paste directly.

Quick Reference

| From | To | Converter | |------|-----|-----------| | CSV | JSON | CSV to JSON | | JSON | CSV | JSON to CSV | | JSON | YAML | JSON to YAML | | YAML | JSON | YAML to JSON | | XML | JSON | XML to JSON | | JSON | XML | JSON to XML | | Markdown | HTML | Markdown to HTML | | TSV | JSON | TSV to JSON |

Need to go from YAML to CSV? Convert YAML to JSON first, then JSON to CSV. Two clicks, still free.

Privacy and Security

Every tool on this page runs entirely in your browser. Here's what that means:

• Passwords you generate are created using crypto.getRandomValues() — the browser's cryptographic random number generator. They're never transmitted anywhere.
• JWTs you decode stay on your device. We can't see your tokens.
• Hashes you generate are computed locally. SHA hashes use the Web Crypto API; MD5 uses a pure JavaScript implementation.
• Text you paste into any tool is processed in JavaScript on your machine. There are no API calls, no server-side processing, no logging.

We don't run analytics on individual tool usage. We don't store what you paste. The tools work offline once the page is loaded.

What's Coming

We have more developer tools in the pipeline:

• Regex Tester — with live match highlighting
• Text Diff — side-by-side comparison of two texts
• Color Palette Generator — harmonious color schemes from a base color

These need custom UI components beyond our standard tool layout, so they're taking a bit longer. They'll be free and browser-based, same as everything else.