Free Developer Tools & Hardware Tests
Format JSON, decode Base64 or JWTs, generate UUIDs and convert epoch times. Test your camera, mic, speakers, keyboard or mouse. Free, with no signup and your input kept on your device.
21 tools available
Color Picker & Converter
Pick colors and convert HEX, RGB and HSL values with alpha transparency.
Open toolContrast Checker
Compare foreground and background colors against WCAG AA and AAA text thresholds.
Open toolURL Encoder / Decoder
Encode or decode URL components, complete URLs and form query values locally.
Open toolRegex Tester
Test JavaScript regular expressions with flags, match offsets, capture groups and cancellation.
Open toolQR Code Generator
Generate a QR code from text or a URL locally and download a PNG with selectable error correction.
Open toolImage Resizer
Resize a local still PNG, JPEG or WebP by dimensions or percentage and download the result.
Open toolPassword Generator & Strength Checker
Generate random passwords using browser cryptography and review local length and pattern warnings.
Open toolText Diff
Compare two texts locally and inspect added, removed and unchanged lines with whitespace controls.
Open toolSHA Hash Generator
Calculate SHA-256, SHA-384 or SHA-512 hashes for UTF-8 text or a bounded local file.
Open toolJSON Formatter
Format, validate, minify and explore JSON in a tree viewer locally.
Open toolBase64 Encoder / Decoder
Encode text or files to Base64, or decode standard and URL-safe data.
Open toolUUID Generator
Generate UUIDs and GUIDs in bulk with v1, v4, v6 and v7 options.
Open toolUnix Timestamp Converter
Convert Unix and epoch timestamps to dates and back, in seconds or milliseconds.
Open toolJWT Decoder
Decode JSON Web Token headers, payloads, claims and expiration dates locally.
Open toolScreen Resolution
Inspect browser-reported screen size, viewport dimensions and device pixel ratio.
Open toolDead Pixel Test
Inspect your display manually using solid white, black, red, green, blue and gray patterns.
Open toolWebcam Test
Run a camera test with a live webcam preview, resolution details and local snapshots.
Open toolMicrophone Test
Run a mic check, view microphone input levels and record a short clip for playback.
Open toolSpeaker Test
Check speakers or headphones with a gentle melody or plain stereo test tone.
Open toolKeyboard Test
Use a keyboard tester to check physical keys, held states and repeat events.
Open toolMouse Test
Test mouse buttons, browser double-clicks, scroll wheel events and pointer movement.
Open toolNo tools match your search. Try “mic check”, “keyboard tester”, “JSON” or a different category.