ByteScope
Free online developer tools — no install, no signup. Everything runs in your browser, so your files never leave your device.
Your files never leave your browser.
TYPE QUEST — playable demo
Type the code. Watch it come alive.
A typing game where every keystroke builds a real, runnable mini project — while it clocks your typing speed. The faster you type, the faster you write code. Try this one right here.
every character you type builds this pane — the finished code runs right here
Tools
Image tools
Image ↔ Base64 Converter
Batch convert images to Base64 data URIs — and decode Base64 back to images.
● live · /image-base64
Compress Image
Type the size you need — 200 KB, 1 MB, 5 MB — and the quality is searched until the file fits.
● live · /image-compress
Image Format Converter
Batch convert between PNG, JPEG, WebP, AVIF and GIF — with live size feedback.
● live · /image-convert
Image Pixel Diff
Compare two images pixel by pixel — diff, blend, swipe, onion skin and blink.
● live · /image-diff
Image Inspector
Magnify, pick pixel colors, and record sample points — HEX, RGB, HSL and OKLCH.
● live · /image-inspector
EXIF Viewer
Read every EXIF tag in a photo — body, lens, exposure, the software field and GPS coordinates — without the file leaving your browser.
● live · /exif-viewer
Remove EXIF
Strip EXIF, GPS and IPTC from iPhone HEIC, JPEG, PNG, WebP and AVIF photos — the pixels come out bit-identical, because nothing is ever re-encoded.
● live · /remove-exif
Remove Video Location
Find where a video says it was filmed, and clear it — without re-encoding, without uploading, and with a report of what was and was not checked.
● live · /remove-video-location
Redact Screenshot
Paste a screenshot, cover the private parts, copy it straight back — with no blur on offer, because blurred text can be reconstructed.
● live · /redact-screenshot
Blur Faces
Find the faces in a batch of photos, check every picture yourself, then cover them with a solid block or a coarse mosaic — no blur on offer, because a light blur can be undone.
● live · /blur-faces
AI Image Upscaler
Make a small picture bigger with an AI model that runs in this tab — drop it in, pick 2x or 4x, drag to compare against plain stretching, and download. Nothing is uploaded.
● live · /upscale-image
Image to SVG
Trace a logo, illustration or drawing into clean SVG paths — choose a preset, tune the colours, fix the palette, and download. Nothing leaves your browser.
● live · /image-to-svg
Screenshot Beautifier
Paste a screenshot, give it a gradient or blurred background, rounded corners, a shadow and a window frame, then download or copy it — nothing leaves your browser.
● live · /screenshot-beautifier
Similar Photo Finder
Pick a folder, let it group the bursts, resized copies and re-saved shots, keep the best of each group and move the rest aside — all in your browser, nothing uploaded.
● live · /similar-photos
Portrait Blur
Portrait mode for photos that never had it: an AI depth model runs in this tab, you tap to refocus, and nothing is uploaded.
● live · /portrait-blur
ID Photo Maker
Six verified sizes, guides you line yourself up with, and a 4×6 sheet to print.
● live · /id-photo
Batch Image Converter
Batch convert entire folders of images between formats — locally, with zero uploads.
● live · /batch-image-convert
Photo Organizer
Sort photos by EXIF capture date into organized folders and separate screenshots.
● live · /photo-organizer
Photo Date Fixer
Wrong camera clock or time zone? Shift every photo's EXIF date by the same offset, keep a record, and never touch the pixels.
● live · /photo-date-fix
Remove Background
Cut a subject out locally. No account, no upload, a transparent PNG when you are done.
● live · /remove-background
Restore Old Photos
Sharpen a faded print and, if you want, give it colour — without handing it to a stranger's site.
● live · /photo-restore
Image to Text
Chinese OCR that stays on this device — receipts, phone photos, no account.
● live · /image-to-text
Image to Excel
A table in a screenshot becomes a grid you can edit and an Excel file — without the image leaving this device.
● live · /image-to-excel
Alt Text Generator
Drop in the images from a post and get a draft alt text for each one, written on your machine by Florence-2. Read every draft before you ship it — the model does not know your article, and it can be wrong.
● live · /alt-text-generator
Math OCR
Paste a screenshot of one formula, get LaTeX you can edit while the preview updates. Printed formulas were right 39 times out of 40 in our test; handwriting is untested and usually worse.
● live · /math-ocr
Eyedropper
Pick any color from your screen into hex, rgb, hsl, and oklch with WCAG contrast and palette export.
● live · /eyedropper
Video tools
Subtitle Converter
Convert, retime and repair subtitle files — SRT ↔ VTT ↔ ASS ↔ SBV, locally.
● live · /subtitle-converter
Video Info Inspector
Drop a video, get the full spec sheet — and the reason it won't play somewhere.
● live · /video-info
Video Trimmer
Cut the start and end off a video in seconds — same quality, nothing uploaded.
● live · /video-trim
Rotate Video
Turn a sideways video the right way up in seconds — same quality, nothing uploaded.
● live · /rotate-video
Video Speed
Make a video faster or slower in seconds — picture untouched, nothing uploaded.
● live · /video-speed
Mute Video
Remove the sound from a video in seconds — picture untouched, nothing uploaded.
● live · /mute-video
Merge Videos
Join several clips into one in seconds — no re-encoding, nothing uploaded.
● live · /merge-videos
Compress Video
Shrink a video to the size you need — encoded in your browser, never uploaded.
● live · /compress-video
Burn Subtitles into Video
Hardcode subtitles into the picture with a live preview — re-encoded in your browser, nothing uploaded.
● live · /burn-subtitles
Vertical Video Converter
Make a landscape video fit a phone screen — blurred background, encoded in your browser, never uploaded.
● live · /vertical-video
Extract Audio from Video
Keep only the sound — copied out of the video untouched, or decoded to WAV.
● live · /extract-audio
Screen Recorder
Record your screen — free, no watermark, no install, nothing uploaded.
● live · /screen-recorder
Subtitle Sync
Late subtitles get a shift, drifting subtitles get a two-point stretch — fixed locally, nothing uploaded.
● live · /subtitle-sync
Batch Video Converter
Batch convert GIF animations and MP4 videos across entire folders — locally.
● live · /batch-video-convert
Video Subtitles
A local Whisper model or Chrome's Gemini Nano turns a recording into SRT or VTT — optionally bilingual — and the file never leaves this tab.
● live · /video-subtitles
Subtitle Translate
Translate a YouTube transcript or an SRT/VTT file in this tab — pick the engine, get bilingual output, upload nothing.
● live · /subtitle-translate
Codec Check
HEVC browser support test and AV1 codec check — hardware vs software decode, in this tab.
● live · /codec-check
DRM Check
Widevine test and DRM check — L1, L2 or L3, HDCP 2.2, and the Netflix 480p problem, in this tab.
● live · /drm-check
PDF & Office documents
Merge PDF
Drop several PDFs, put them in order, take whole files or just some pages — merged in this tab, nothing uploaded.
● live · /pdf-merge
Split PDF
Cut a PDF into parts, pull out the pages you need, or drop the ones you don't — planned first, then done in this tab, nothing uploaded.
● live · /pdf-split
Sign PDF
Open a PDF, fill its fields, drop your signature where it belongs — drawn, typed or photographed — and download. Signed in this tab, nothing uploaded.
● live · /pdf-sign
Images to PDF
Turn receipts, ID scans and photos into a single PDF — page size, fit and margins are yours to set, and nothing leaves this tab.
● live · /images-to-pdf
Document Scanner
Open the camera or pick photos, let the page find the four corners (or drag them yourself), straighten the page and lift the shadows — then save every page as one PDF or as JPEGs, entirely in your browser.
● live · /document-scanner
Remove PDF Metadata
Open a PDF, see every Info dict field and the XMP stream, then strip what you don't want to keep — in this tab, nothing uploaded.
● live · /pdf-metadata
Office Document Inspector
Open a .docx, .xlsx or .pptx and see what it carries besides the content you wrote — author names, tracked changes, hidden sheets, cropped originals — then clear the metadata, all in this tab.
● live · /office-inspector
Metadata Check
Drop a whole folder before you send it: every file is identified by its bytes, checked by the same inspector as its own page and summed up in one list — then cleared in batch with a before-and-after check, all in your browser.
● live · /metadata-check
Device & connection diagnostics
My Computer Specs
What are my computer specs? Open this page and see the GPU your browser is using, whether hardware acceleration is on, WebGPU features, CPU threads, RAM, OS version and screen — each value marked measured, estimated or not exposed — then test whether this machine can run local AI.
● live · /my-computer-specs
Display & Monitor Test
Check your screen for defects and read out what your display really supports.
● live · /screen-test
Webcam Test
See your camera working — and what resolution and frame rate it really delivers.
● live · /webcam-test
Video Call Check
Three steps, one verdict: you're ready for the meeting — or here's exactly what to fix.
● live · /call-ready
Keyboard Tester
Press every key, watch it light up — and catch rollover limits and chattering switches.
● live · /keyboard-test
Gamepad Tester
Plug in a controller, press a button — then measure what your sticks are really doing.
● live · /gamepad-test
WebRTC Connection Tester
Not just "does WebRTC work" — see why it doesn't, and what to do about it.
● live · /webrtc-test
Printer Test Page
One sheet that shows what your printer is doing wrong — color, black ink, alignment and hairlines, printed straight from the browser's own dialog.
● live · /print-test-page
Mouse Test
Five buttons, a chatter histogram, a notch-exact wheel counter and an honest polling-rate estimate — one bench for the mouse you're about to blame.
● live · /mouse-test
Speaker Test
Left, right, sweep, pan and bass — a bench of test tones for the speakers you just wired up, generated live in the browser with nothing to download.
● live · /speaker-test
Headphone Test
Swapped sides, a quieter ear, bass that never shows up — check a new pair of headphones before the return window closes, straight from the browser.
● live · /headphone-test
Live Captions
Captions for what you say — or for what your computer is playing: pick a speech engine, add on-device translation, and float the captions over a full-screen slide deck or stream.
● live · /live-captions
Keep Screen Awake
Keep the screen on in this tab — prevent the screen from sleeping with a screen wake lock. No sleep online; coverage shown when the tab is backgrounded.
● live · /keep-screen-awake
Touch Test
Touch screen test in this tab: multi-touch trails, a dead-spot grid, and browser event sample rate. Test touch screen response with a finger or a mouse.
● live · /touch-test
Phone Sensor Test
Is my gyroscope drifting? Why does the compass spin? How accurate is my GPS, really? Open this page on your phone and test the accelerometer, gyroscope, compass, GPS and vibration motor one card at a time, with a bubble level and the sample rate the browser actually delivers — on iPhone and Android, nothing installed, nothing uploaded.
● live · /phone-sensor-test
Pen Pressure Test
Test drawing tablet and stylus pen pressure online: live pressure curve, tilt angles, twist, and estimated hardware pressure levels.
● live · /pen-pressure-test
Built-in AI Test
Probe Translator, Summarizer, Language Detector and Prompt API in this tab — nothing uploaded.
● live · /built-in-ai-test
HDR Test
HDR test online — is this screen really HDR? The numbers follow the window onto another display.
● live · /hdr-test
Hardware bench
Serial Monitor & Plotter
Talk to a dev board over USB serial — terminal, HEX dump and live plots, right in the browser.
● live · /serial-monitor
ESP Firmware Flasher
Flash ESP32 / ESP8266 firmware straight from your browser — detect the chip, write .bin files, back up flash. No IDE, no esptool install.
● live · /esp-flasher
Firmware Installer
Install popular open-source firmware on an ESP board in one click — connect over USB, pick a version, done.
● live · /install
MicroPython Web IDE
Program MicroPython and CircuitPython boards from the browser — REPL, code editor and file manager, nothing to install.
● live · /micropython
MIDI Tester & Monitor
Plug in a MIDI keyboard or controller and see every note, knob and pedal in real time.
● live · /midi-test
Web ADB Toolkit
Talk ADB to your Android over USB from the browser — device info, files, APK sideload, live logcat and a shell.
● live · /web-adb
AVR / Arduino Uploader
Flash a compiled .hex to an Arduino Uno, Nano or Mega straight from the browser — STK500 over Web Serial, with read-back verify.
● live · /avr-uploader
Serial Protocol Playground
Send arbitrary bytes over serial, capture the reply, and reverse-engineer the protocol — right in the browser.
● live · /serial-playground
HID Report Descriptor Inspector
Plug in a HID device and read exactly what it tells the host — the decoded descriptor, a bit-level field map and live input reports.
● live · /hid-inspector
BLE GATT Explorer
Connect to any BLE device and walk its GATT tree — read, decode, write and subscribe, right in the browser.
● live · /ble-explorer
USB Device Identifier
Type a VID/PID and get the names behind it, or plug a device in and read every descriptor the browser will show you.
● live · /usb-device-info
USB Format Guide
Pick your OS and what the drive is for to see the commands, then type your disk number to unlock copying. This page never touches your drive — you run the commands, after checking the disk number twice.
● live · /format-usb-guide
NFC Reader
NFC tag reader online — write an NFC tag without an app, in Android Chrome. Local only.
● live · /nfc-reader
Image to C Array
Both directions: a picture into an array your firmware compiles, and an array back into a picture you can actually look at.
● live · /image-to-c-array
Intel HEX Converter
Read a firmware image line by line, see exactly where every byte lands, and write it back out in whatever container your flasher wants.
● live · /intel-hex-converter
Web ADB workstation
● live · /web-adb/*
One USB cable, thirteen pages: everything below talks ADB straight from the browser, with nothing installed on the phone.
Other tools
APK Analyzer
Inspect an Android APK's manifest, permissions, signature, symbols and code — locally.
● live · /apk-analyzer
Hex Viewer / Editor
View and edit binary files in your browser — hex, decimal or binary, vim-style.
● live · /hex-editor
Password Generator
Strong random passwords, passphrases and PINs — generated locally, never transmitted.
● live · /password-generator
File Hash Calculator
Hash files with every common algorithm at once and verify checksums — locally.
● live · /file-hash
File Type Identifier
Find out what a file really is — magic-number detection, locally.
● live · /file-type
Timestamp Converter
Unix time ↔ human time, with the timezones you care about side by side.
● live · /timestamp
Archive Inspector
See exactly what's inside an archive — without extracting it or uploading it.
● live · /archive-inspector
Extract Archive
Unpack zip, rar, 7z and tar.gz right in the browser — passwords stay local, and dangerous paths are stopped at the door.
● live · /extract-archive
SQLite Viewer
Browse tables, run queries, build them visually — your database stays on your machine.
● live · /sqlite-viewer
Certificate Decoder
Paste a certificate, read everything in it — and find out why the chain is broken.
● live · /certificate-decoder
Certificate Generator
Self-signed certs, CSRs and a browser-based local CA — private keys never leave your machine.
● live · /certificate-generator
Type Quest
Type real code, watch it come alive next to you — and find out how fast you really type.
● live · /type-quest
QR File Transfer
Beam a file from one screen to another camera — no network, no cable, no pairing, no account. Just light.
● live · /qr-file-transfer
Subnet Calculator
Paste a CIDR, a bare address, or an address and a netmask — IPv4 and full IPv6, all in your browser.
● live · /subnet-calculator
Bitwise Calculator
AND, OR, XOR, shifts and a clickable bit grid — plus a bitfield decoder for the register in front of you.
● live · /bitwise-calculator
Binary Diff
Drop in two firmware builds, two disk images or two config dumps — byte-level comparison, entirely in your browser.
● live · /binary-diff
TOTP Generator
Paste a base32 secret or an otpauth:// URI and get the rolling six-digit code with a countdown ring — computed in your browser, never sent anywhere.
● live · /totp-generator
Online Ruler
A ruler on your screen that is actually the right size — calibrate with a credit card, then trust the millimetres.
● live · /online-ruler
Bulk Rename
Pick a folder on your disk, stack up rename rules, preview every old name against its new one, then apply in place — from a web page, with nothing uploaded.
● live · /bulk-rename
Duplicate File Finder
Walk a folder, group files by size, hash only the candidates, and delete the copies you choose — locally, and knowing that deleted really means deleted.
● live · /duplicate-finder
VCF to CSV Converter
Turn a .vcf contact export into a CSV that Excel opens cleanly — and back again. Your contact book never leaves the browser.
● live · /vcf-to-csv
ICS Viewer
Read an .ics calendar file: every event laid out as a list, a month view, and a CSV you can open in a spreadsheet. The file never leaves your browser.
● live · /ics-viewer
GPX & FIT Viewer
Read a watch or bike computer's GPX or FIT recording: summary, track and charts in one place, FIT to GPX and CSV export, all inside your browser. The file never leaves your machine.
● live · /gpx-viewer
MSG Viewer
Read a .msg file someone sent you without installing Outlook: the header, both bodies and every attachment, downloadable. The file never leaves your browser.
● live · /msg-viewer
EML Viewer
Read a raw .eml message without a mail client: the whole header block, both bodies and every attachment, downloadable. The file never leaves your browser.
● live · /eml-viewer
Email Header Analyzer
Paste the raw headers from Gmail's "Show original" or Outlook's message properties, or drop an .eml or .msg file. The page lists every Received hop with its delay, explains each Authentication-Results line, and re-verifies the DKIM signature itself with the sender's public key. The message never leaves your browser.
● live · /email-header-analyzer
Email DNS Check
Type a domain and get one card per record — MX, SPF, DMARC, DKIM, BIMI, MTA-STS and TLS-RPT — each with the current state, why it matters and how to fix it, including example records you can paste into DNS. The SPF tree shows every include and counts the lookups against the limit of 10. No score, no sign-up.
● live · /email-dns-check
CSV Explorer
Open the CSV Excel refuses — gigabytes, millions of rows — and browse, sort, filter and query it. The file is read off your disk and never uploaded.
● live · /csv-explorer
Parquet Viewer
Open a .parquet file without Python: see the schema and first rows at once, run SQL on it, export to CSV. Read from your disk, never uploaded.
● live · /parquet-viewer
Large File Viewer
Open the 3 GB log that Notepad and VS Code give up on: scroll at once, search, filter like grep, read JSONL line by line. Nothing is uploaded.
● live · /large-file-viewer
Device Transfer
Files and whole folders straight from one device to another, over a link the two of them make between themselves.
● live · /device-transfer
Voice Notes
Record microphone or meeting audio with live transcripts and translation — your choice of speech engine, all in the browser.
● live · /voice-notes
Text to Speech
Paste any amount of text, pick a voice, listen — and when you like it, download a WAV. Three engines: your system's built-in voices with nothing to download, Kokoro 82M for Chinese and Supertonic 3 for English and Japanese. Everything is synthesised in the browser; your text stays on your device.
● live · /text-to-speech
Audio Denoise
Drop a voice recording — or a video, its audio track is used — and hear the first 15 seconds cleaned within moments. Flip between Original and Denoised without losing your place, set how much noise to remove, then download a WAV of the same length. RNNoise runs as WebAssembly in a Web Worker; the file never leaves your computer.
● live · /audio-denoise
Loudness Normalizer
Drop a recording — or a video, its audio track is used — and read its integrated loudness, loudness range and true peak at once. Pick a target such as -16 LUFS, download a WAV, and see the re-measured result next to the target. The file never leaves your computer.
● live · /loudness-normalize
Silence Remover
Drop a recording — or a video, its audio track is used — and see the pauses shaded on a waveform. Set the threshold and minimum silence length, click any cut to keep it, play the result before exporting, then download a WAV or an EDL, FCPXML or CSV cut list for your editor. The file never leaves your computer.
● live · /remove-silence
BPM & Key Finder
Drop a batch of songs and read the tempo, key, Camelot and Open Key code and the runner-up key off one table. Each track is analysed in a Web Worker in your browser — nothing is uploaded. Correct a tempo by tapping along, then export CSV or copy JSON for your set list or spreadsheet.
● live · /bpm-key-finder
Audio to MIDI
Drop a recording or hum into the microphone: an AI model finds the notes in this tab, you check them on a piano roll and download a .mid file.
● live · /audio-to-midi
Chat Export Viewer
Drop the zip from a ChatGPT or Claude data export — or just conversations.json — and read your whole history in one place: search across every message, flip between edited or regenerated branches, see how much you talked and when, and save one conversation or all of them as Markdown. Everything happens in this browser tab; nothing is uploaded or stored.
● live · /chat-export-viewer
WhatsApp Chat Viewer
Drop the .txt or the zip that WhatsApp's Export Chat produced and read it like a chat again: your messages on the right, theirs on the left, photos, videos and voice notes playing from the file, search, per-person statistics and Markdown or CSV export. Everything runs in this browser tab; nothing is uploaded or stored.
● live · /whatsapp-chat-viewer
HLS / M3U8 Player
Paste an m3u8 URL, watch it play — and find out exactly why it does not.
● live · /hls-player
ELF Inspector
Open an ELF, read every structure — the binary never leaves this tab.
● live · /elf-inspector
Anonymize Text
Before you paste text into an AI, swap names, phone numbers, emails and ID numbers for numbered tokens. Put the originals back in the reply. Everything happens in your browser.
● live · /anonymize-text
Encrypt File
Password-encrypt a file in this tab — AES-256-GCM as compact JWE, nothing uploaded.
● live · /encrypt-file
Folder Hash
Walk a folder, write a standard SHA256SUMS file, or drop a checksum file and list matched, mismatched, missing and extra paths — locally.
● live · /folder-hash
Create ZIP
Pick files or a folder, stream a ZIP to disk on Chromium, or download a size-capped archive — locally, nothing uploaded.
● live · /zip-create
Folder Compare
Pick two folders and list only-in-A, only-in-B, and files whose contents differ — size first, then streaming SHA-256, locally.
● live · /folder-compare
Folder Size
Pick a folder and see where the bytes went — a treemap, the largest files, and an extension breakdown. Read-only, nothing uploaded.
● live · /folder-size
Barcode Scanner
Scan barcodes with your camera online: real-time detection, instant inventory counts, editable names, and CSV export.
● live · /barcode-scanner
Clipboard Inspector
Clipboard viewer — every MIME type, raw HTML, hex dump. Local, on a click, then gone.
● live · /clipboard-inspector
HAR File Sanitizer
Drop a .har from DevTools and see every cookie, Authorization header, token, JWT and private key it carries — then download a copy with the values replaced, before you hand it to support or paste it into an issue.
● live · /har-sanitizer
Invisible Character Checker
Paste text or drop a file and see every character that does not show on screen — zero-width spaces, bidi overrides, Unicode tags, odd spaces, Cyrillic letters hiding in a Latin word — each as a badge with its code point, then remove the ones you choose.
● live · /invisible-characters
HTTP Status Code Reference
What each HTTP status code means — and what the front end, the back end and the visitor each do about it.
● live · /http-status
Port Number Reference
What runs on a port, whether it belongs on the internet, and how to find the process holding it.
● live · /port
Excel Compare
Compare Excel sheets for differences without uploading them: changed values, swapped-out formulas and type changes flagged cell by cell, rows lined up by a key column, automatically or by position — all inside your browser.
● live · /excel-compare
Word Compare
Word compare without Office: drop two `.docx` files and read the redline — added and deleted text marked paragraph by paragraph and word by word — without either file leaving your browser.
● live · /word-compare
CRC Calculator
One input, 113 published CRCs, and a search that names the one your device is using.
● live · /crc-calculator
Firmware Inspector
The first pass over an unknown image: which parts are compressed, what is embedded in it, and what it says about itself.
● live · /firmware-inspector
Agent Cost
Claude Code already totals one session. This page sums every project: cache split, what-if, and the files that cost the most.
● live · /agent-cost
LLM Pricing
Per-million token rates, a cache-hit slider, and the day the card was checked.
● live · /llm-pricing
Context Cost
How many tokens a repo is, what that context window costs, and what the rules files repeat.
● live · /context-cost
ByteScope MCP
Fully offline. One npx line gives a coding agent real hashes, file types, certificate and pcap decoding, test files and id lookups.
● live · /mcp
Test File Generator
Pick a format, set the options, download a small valid file. It is built in this tab.
● live · /test-files
AI Crawler Log
Which AI crawlers visit, what they read, and which pages they never touch.
● live · /ai-crawler-log
llms.txt Generator
Turn your sitemap into an llms.txt you can publish today.
● live · /llms-txt-generator
Serverless Cost
Describe what your Worker does. See which Free limit breaks first, what Paid costs, and what changes at ten times the traffic.
● live · /serverless-cost