The Developer Tool Belt

A growing collection of free, fast, privacy-first web utilities. Everything runs in your browser — your data never leaves your device.

Converters

Base64 to Image

Decode Base64 strings to PNG, JPG, GIF, WebP or SVG images.

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Image to Base64

Encode any image to a Base64 string for CSS, HTML, or JSON.

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Base64 to PDF

Decode Base64 strings into downloadable PDF files.

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PDF to Base64

Encode PDF files to Base64 for JSON, APIs, or data URLs.

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Base64 to Hex

Convert Base64 strings to lowercase hexadecimal.

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Hex to Base64

Convert hexadecimal strings to standard Base64.

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Markdown ↔ HTML Converter

Convert Markdown to HTML and HTML to Markdown with GitHub-flavored extensions, live preview, and sanitization.

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JSON ↔ CSV Converter

Convert JSON to CSV and CSV to JSON with flatten, delimiter, RFC 4180 escaping, and auto-typing.

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JSON ↔ YAML Converter

Convert JSON to YAML and YAML to JSON — lossless, configurable indent, sort keys, and flow style.

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CSV ↔ YAML Converter

Convert CSV to YAML and YAML to CSV with delimiter, flatten nested fields, and auto-typing.

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Color Picker & Converter

Pick, convert, and explore colors between HEX, RGB, and HSL with contrast checking and harmonies — all in your browser.

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Number Base Converter

Convert between binary, octal, decimal, and hexadecimal with bit visualization and all outputs at once — all in your browser.

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Timestamp / Epoch Converter

Convert Unix timestamps to human-readable dates and vice versa. Supports seconds, milliseconds, microseconds, and nanoseconds — all in your browser.

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Decimal Converter

Convert between decimal, binary, octal, and hex — and see the ASCII character.

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Binary Converter

Convert binary to decimal, hexadecimal, octal, and ASCII — instantly and privately.

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ASCII Table & Converter

Browse the full 128-character ASCII table and convert between char, decimal, hex, binary, octal, and HTML entity.

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Generators

JWT Encoder & Token Generator

Generate and sign JSON Web Tokens (HS256/384/512) locally in your browser.

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Regex Generator

Build regular expressions visually with blocks, quantifiers, presets, and live match preview — all in your browser.

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Regex Tester & Debugger

Test regular expressions with real-time match highlighting, capture groups, and replacement preview — all in your browser.

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Diff Checker & Text Compare

Compare two texts side by side or unified — spot every addition, deletion, and change instantly and privately.

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File Compare

Compare two files by SHA-256 hash and see a line-by-line diff for text files — all in your browser.

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UUID / GUID Generator

Generate RFC 4122 UUID v4, v1, and GUIDs with multiple format options and validation — all in your browser.

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Password Generator

Generate strong, random, and memorable passwords with adjustable length, character sets, and strength meter — all in your browser.

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Lorem Ipsum Generator

Generate paragraphs, sentences, words, and lists of classic placeholder text — instantly and privately in your browser.

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Fake Data / Mock JSON Generator

Build custom schemas and generate realistic mock data — JSON, JSON Lines, CSV, or SQL INSERT — all in your browser.

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QR Code Generator

Generate QR codes for URLs, text, email, WiFi, and contacts. Customize size, colors, and error correction. Download PNG or SVG — all in your browser.

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Random Number Generator

Generate cryptographically secure random integers, floats, sequences, and dice rolls — all in your browser.

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Cron Expression Generator

Build, parse, and explain cron schedules with live next-run previews — all in your browser.

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Color Palette Generator

Generate harmonious color palettes with lockable swatches and export to CSS, SCSS, JSON, or Tailwind — all in your browser.

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Formatting

JSON Formatter & Beautifier

Format, beautify, minify and validate JSON with sort keys, ASCII escape, and tree view.

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JSON Validator

Strict JSON validator with precise error location, lint hints, structure stats, and duplicate key detection.

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JSON Viewer

Interactive JSON tree explorer with filter, copy-path, expand/collapse all, and colour-coded types.

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JSON Editor

Visual JSON tree editor — rename keys, change types, add or delete nodes, with undo/redo and export.

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JSON Diff & Compare

Compare two JSON documents semantically — added, removed, and changed keys with exact JSON paths.

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HTML Formatter & Beautifier

Beautify or minify HTML with configurable indent, line wrap, and inline-tag handling.

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HTML Minifier

Minify HTML with advanced options: remove comments, collapse whitespace, minify inline CSS & JS, remove optional closing tags.

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CSS Formatter & Beautifier

Beautify or minify CSS with configurable indent, blank lines between rules, and selector formatting.

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CSS Minifier

Minify CSS with advanced options: remove comments, collapse whitespace, shorten hex colors, remove zero units, and more.

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JavaScript Formatter & Beautifier

Beautify or minify JavaScript with configurable indent, preserve newlines, chained methods, and array indentation.

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JavaScript Minifier

Minify JavaScript with advanced options: remove comments, collapse whitespace, strip console.log, shorten booleans, and more.

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SQL Formatter & Beautifier

Beautify or minify SQL with configurable indent, keyword case, and clause formatting — all in your browser.

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XML Formatter & Validator

Beautify, minify, and validate XML, SVG, RSS, and SOAP with configurable indent — all in your browser.

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