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Developer Tools

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Formatters

JSON Formatter HTML Formatter CSS Formatter JS Formatter SQL Formatter XML Formatter YAML Formatter

Encoders / Decoders

Base64 URL Encode/Decode HTML Entities JWT Decoder Base32 Encode/Decode Base58 Encode/Decode ROT13 / ROT47 Cipher CRC32 Checksum Punycode Converter Quoted-Printable

Converters

JSON to YAML JSON to CSV XML to JSON JSON to TypeScript JSON to Python JSON to Java JSON to C# JSON to Go JSON Schema Generator SQL to JSON Query String Converter Number Base Unix Timestamp Case Converter Text to HTML CSV to Markdown HTML to Markdown

Generators

UUID Generator Hash Generator Password Generator Lorem Ipsum QR Code QR Code Scanner Barcode Generator Slug Generator Meta Tag Generator Placeholder Image HTML Table Generator Markdown Table Generator robots.txt Generator .htaccess Generator Mock Data Generator README Generator Random Number Generator

Testers

RegEx Tester Text Diff Markdown Preview String Inspector JSON Path Evaluator CSV Viewer JSON Tree Viewer Live Code Preview SVG Preview JSON Compare Responsive Tester

CSS Visual Tools

Gradient Generator Box Shadow Generator Flexbox Playground Grid Generator CSS Unit Converter Border Radius Text Shadow Animation Generator Filter Generator Transform Generator Clip Path Generator Multi-Column Glassmorphism Generator Neumorphism Generator CSS Loader Generator CSS Button Generator Cubic Bezier Editor CSS Blob Generator

Colors & Accessibility

Color Picker Color Converter Palette Generator Contrast Checker Color Blindness Simulator Shades & Tints Generator Color Name Finder

Text Utilities

Line Sort/Dedupe Escape/Unescape URL Parser Word Counter Emoji Picker Encoding Detector Find and Replace Whitespace Cleaner Character Counter Text to Binary Morse Code Translator NATO Phonetic Alphabet Online Notepad Text to Speech

Dev Utilities

Cron Parser Cron Expression Builder Chmod Calculator HTTP Status Codes MIME Type Lookup Aspect Ratio Calculator Social Share Preview Font Preview CSS/JS Minifier Pixel Ruler Device Mockup cURL Converter User Agent Parser HTTP Header Analyzer

Calculators

IP Subnet Calculator Binary & Bitwise Calculator Unit Converter Roman Numeral Converter Date & Age Calculator Percentage Calculator Time Zone Converter

SVG Tools

SVG Optimizer SVG to PNG SVG to Data URI SVG Blob Generator SVG Wave Generator SVG Pattern Generator

Project Files

.gitignore Generator License Generator package.json Generator .editorconfig Generator Dockerfile Generator .env Example Generator

Image Editing

Background Remover Crop Image Rotate Image Flip Image Resize Image Image Upscaler Grayscale Image Blur Image Pixelate Image Add Border to Image Watermark Image Add Text to Image Circle Crop Join Images Image Splitter Image Color Picker EXIF Metadata Viewer Remove EXIF Data Image to Text (OCR) Color Palette from Image Signature Maker

Image Converters

Image Converter PNG to JPG PNG to WebP PNG to BMP PNG to GIF JPG to PNG JPG to WebP JPG to BMP JPG to GIF WebP to PNG WebP to JPG WebP to BMP WebP to GIF BMP to PNG BMP to JPG BMP to WebP BMP to GIF GIF to PNG GIF to JPG GIF to WebP GIF to BMP HEIC to JPG HEIC to PNG HEIC to WebP AVIF to JPG AVIF to PNG AVIF to WebP

Image Compression

Compress Image Bulk Image Compressor Increase Image Size Compress to 10 KB Compress to 20 KB Compress to 50 KB Compress to 100 KB Compress to 200 KB Compress to 500 KB Compress to 1 MB Compress to 2 MB

Social Media

SOME Image Resizer Resize to IG Post Resize to IG Portrait Post Resize to IG Landscape Resize to IG Story Resize to IG Profile Photo Resize to FB Post Resize to FB Cover Photo Resize to FB Profile Photo Resize to FB Story Resize to FB Event Cover Resize to X Post Image Resize to X Header Resize to X Profile Photo Resize to YT Thumbnail Resize to YT Banner Resize to YT Profile Photo Resize to LI Post Image Resize to LI Cover Banner Resize to LI Profile Photo Resize to LI Logo Resize to TT Video Cover Resize to TT Profile Photo Resize to PIN Pin Resize to PIN Profile Resize to WA Profile Resize to WA Status

Video Tools

Video Trimmer Video Compressor MP4 to MP3 Video to GIF Video Frame Extractor

Recorders & Device Tests

Microphone Test Webcam Test Voice Recorder Screen Recorder

Meme Tools

Meme Generator Demotivational Poster Video Meme GIF

PDF Tools

Image to PDF Merge PDF Split PDF PDF to Image Compress PDF PDF to Text Rotate PDF Organize PDF Pages Add Page Nr to PDF

GIF Tools

GIF Maker GIF to Frames Add Text to GIF GIF Speed and Reverse

Audio Tools

Audio Cutter Audio Joiner Audio Volume and Fade Audio to WAV Converter Audio Metadata Viewer

Audio Converters

MP3 to WAV OGG to WAV M4A to WAV FLAC to WAV WAV to MP3 OGG to MP3 M4A to MP3 FLAC to MP3

SEO Tools

Favicon Generator Sitemap Generator JSON-LD Schema UTM Link Builder Hreflang Tag Generator

Security & Crypto

AES Encrypt / Decrypt Key Pair Generator HMAC Generator JWT Signer Token Generator

Grayscale & Black and White

Convert a color photo to grayscale, pure black & white, or sepia tone.

Runs entirely in your browser.

Grayscale Image Tool

Drop an image here or click to upload

Supports PNG, JPEG, WebP, GIF, BMP

Grayscale
Black & White
Sepia

About Grayscale Conversion

Grayscale removes all color while keeping brightness. The luminance of each pixel is computed as 0.299×R + 0.587×G + 0.114×B.

Black & white turns every pixel fully black or white based on a threshold, while sepia adds a warm brown tone.

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