ByteKit · Free Online Utility Hub

Free, privacy-first browser tools for developers, writers, designers, and creators. Every tool runs entirely in your browser — no uploads, no accounts, no tracking.

Programmer & Developer Tools

Code Beautifier — Automatically format your JavaScript, CSS, and HTML with customizable indentation and style rules.
Minifier — Reduce bundle sizes by removing whitespace, comments, and optimizing code structure for production.
JSON Diff — Compare two JSON objects structurally to spot added, removed, and changed keys — or switch to line and word mode for plain text and code.
JSON Validator — Validate, parse, and prettify JSON data. Identifies syntax errors with precise line number reporting.
RegEx Tester — Build and test regular expressions in real-time with syntax highlighting and match group visualization.
Base64 Converter — Quickly encode and decode strings or files to Base64 format for safe data transmission.
Cron Generator — Generate cron job expressions using a human-friendly interface. Includes execution schedule preview.
JWT Debugger — Decode and inspect JSON Web Tokens. Verify signatures and view payload data without exposing secrets.
Hash Generator (MD5, SHA-256…) — Compute MD5, SHA-1, SHA-256, and SHA-512 hashes of text or files, and verify downloads against an expected checksum — all on your device.
UUID Generator (v1–v7) & Random String — Bulk-generate UUIDs of every version — random v4, sortable v7/v6, timestamp v1, name-based v3/v5 — plus crypto-random strings with custom characters.
YAML ↔ JSON Converter — Convert between YAML and JSON in both directions with live preview, validation with exact error positions, and multi-document support.
JSON ↔ CSV Converter — Flatten JSON arrays into CSV with column selection and Excel-ready download, or parse CSV back to JSON with type inference.
.env ↔ JSON Converter — Parse .env files to JSON (comments, quotes, multiline values handled) or generate .env from JSON config — entirely in your browser.
QR Code Generator — Turn any text or URL into a QR code — custom colors, error-correction level, and crisp SVG or high-res PNG export. No watermark, no signup.
URL Encoder / Decoder — Percent-encode or decode text, URLs, and query strings — with batch line mode and a parsed parameter breakdown.

Text & Content Utilities

Diff Checker — Compare two blocks of text to find additions, deletions, and subtle changes.
Case Converter — Toggle between camelCase, PascalCase, snake_case, and kebab-case instantly.
Word & Character Counter — Count words, characters, sentences, paragraphs, and estimate reading time.
Lorem Ipsum Generator — Generate placeholder text for layouts — by paragraphs, sentences, or words, with optional HTML output.
Markdown → HTML — Convert Markdown into clean, copyable HTML with a live preview. Supports GFM tables, code blocks, and task lists.
List Randomizer & Sorter — Shuffle, sort, dedupe, reverse, or pick random items from any list.

Calculators & Converters

Margin Calculator — Calculate gross profit, markups, and margins for retail or service pricing.
Epoch Converter — Transform Unix timestamps to human-readable dates and local timezones.
Compound Interest — Project investment growth with recurring contributions across any compounding frequency.
Mortgage Calculator — Compute monthly payments, total interest, and an amortization preview for any loan.
Freelance Tax Estimator — Estimate self-employment and income tax owed on freelance revenue after deductions.
Crypto ROI Calculator — Calculate profit, ROI %, breakeven price, and annualized return for any crypto trade.
BMI Calculator — Compute body mass index from height and weight with WHO category breakdown.
TDEE Calculator — Estimate basal metabolic rate (BMR) and total daily energy expenditure using Mifflin-St Jeor.
Daily Calorie Needs — Target daily calories for losing, maintaining, or gaining weight based on TDEE and goal.
Macro Tracker — Split daily calories into protein, carbs, and fat grams for any diet preset.
Unit Converter — Convert length, weight, data storage, temperature, volume, speed, area, and time.
Currency Converter — Real-time fiat and crypto currency conversion with live exchange rates.
Date Difference Calculator — Days, weeks, months, and years between two dates — plus a business-day mode that skips weekends and your holidays.
Percentage Calculator — Find a percentage of a number, increase or decrease by a percent, what-percent-of, and reverse percentages.

Image & Design Tools

CSS Generator Suite — Visual sliders for gradients, box-shadows, and glassmorphism — copy production-ready CSS.
SVG → PNG Converter — Convert any SVG vector to a PNG raster at custom resolutions, with transparent or solid backgrounds.
Image → SVG (Trace) — Vectorize PNG, JPG, or WebP images into scalable SVG paths with adjustable color palette and detail.
Image Cropper, Resizer & Compressor — Crop to any aspect ratio, resize to exact dimensions, and compress JPG/PNG/WebP — all in your browser.
AI Background Remover — Erase backgrounds from portraits and product photos using a neural network that runs entirely in your browser.
Color Picker & Palette Generator — Pick exact pixel colors from any image with a magnifying loupe, extract its dominant palette, and export as Tailwind, CSS variables, SCSS, or JSON.
Image Watermark — Overlay custom text or a logo on your images with opacity, position, rotation, and tiling controls.
EXIF Viewer & Stripper — Read the EXIF, GPS, and XMP metadata embedded in a JPEG — then strip it out losslessly to protect your privacy.
Image Format Converter — Bulk-convert images between JPG, PNG, WebP, and AVIF with quality controls — download individually or as a ZIP.

PDF & File Management

PDF Toolkit (Merge / Split / Organize) — Combine multiple PDFs, extract page ranges, reorder, rotate, or delete pages — entirely in your browser.
PDF to Images (PNG / JPG) — Render each page of a PDF as a PNG or JPG image with quality and DPI controls — download single pages or all of them as a ZIP.
Image to PDF — Combine multiple images (JPG, PNG, WebP, GIF, BMP) into a single PDF with page-size and orientation options.
PDF Compressor — Shrink PDF file size by downsampling page images or re-streaming with compact object streams and stripped metadata.

Video & Audio Tools

Video Trimmer & Muter — Trim a clip by start/end time or strip the audio track — processed on your device with FFmpeg WebAssembly, no upload.
Video to Audio Converter (Extract MP3) — Extract the audio track from any video as MP3, WAV, M4A, OGG, or FLAC — converted on your device with FFmpeg WebAssembly, no upload.
Audio Cutter & Joiner (MP3 Splitter) — Cut a section out of an audio file or merge multiple tracks into one MP3, WAV, or M4A — processed on your device, no upload.
Video Joiner (Merge Clips) — Combine multiple video clips into one file — fast stream-copy for same-source clips or re-encode for mixed formats, all in your browser.
Add Audio to Video — Attach one or more audio tracks to a video — replace the soundtrack or mix music and narration over the original sound, with no upload.
Video to GIF Converter — Turn a video clip into a high-quality animated GIF — pick the section, size, and frame rate; converted on your device, no upload.
Voice & Screen Recorder — Record your microphone, screen, or webcam right in the browser — pause/resume, live preview, instant download. Nothing leaves your device.
Audio Speed & Pitch Changer — Slow down or speed up audio without chipmunk effect, or shift the pitch by semitones without changing tempo — all on your device.
Video Frame Extractor (Video to Image) — Grab any frame of a video as a full-resolution PNG, JPEG, or WebP image — frame-step to the exact moment, all on your device.
Volume Booster & Normalizer — Boost quiet audio by up to 20 dB without clipping, or normalize tracks to streaming/podcast loudness standards — all on your device.
Audio Format Converter — Convert audio between MP3, WAV, M4A, OGG, FLAC, and OPUS — batch-convert multiple files on your device, no upload.