Tool Directory
Tools
Organized by category with fast keyword filtering.
PGlite SQL Sandbox
Use a lightweight SQL sandbox for queries, backup import/export, and keeping the current session data available locally.
SQLite SQL Sandbox
Use a SQLite SQL sandbox for queries, local persistence, and database file import or export.
DuckDB Analytics Sandbox
Use a DuckDB analytics sandbox for analytical SQL, aggregate experiments, and database file import or export.
Parquet / CSV / JSONL Data Workbench
Upload local Parquet, CSV, and JSONL files to inspect schema, preview rows, and run instant SQL analysis.
FC Emulator
Import a local `.nes` ROM and run it directly in the browser, with pause, reset, screenshot, and save-state import/export support.
Arcade Emulator
Import a local arcade ROM, add a BIOS set or parent ROM when needed, and start playing common arcade games quickly.
PDF Text Extraction / Split Merge / Page Image Export
Handle PDF text extraction, page splitting, PDF merge, and page image export directly in the browser.
Image EXIF / Metadata Viewer & Cleaner
Inspect image EXIF, GPS, and authoring metadata in the browser, then export a cleaned copy.
Local Ebook Reader
Open TXT, PDF, and EPUB directly in the browser with page-turn motion, eye-comfort themes, and saved reading progress.
File Digest / Password Hash Lab
Compute file digests, password hashes, and verification results in the browser with SHA, BLAKE3, Argon2id, bcrypt, scrypt, and PBKDF2.
FFmpeg Media Toolkit
Extract audio, trim media clips, export poster frames, and create GIFs directly in the browser with local-only processing.
Local Data Cleaning Tool
Upload local CSV, JSONL, and Parquet files, prune columns, clean strings, filter empty rows, convert empty strings to null, deduplicate, and export the result.
AES Text Encrypt / Decrypt
Encrypt and decrypt text in the browser with AES-GCM or AES-CBC, using either passphrase-derived keys or raw keys with copyable payload output.
JWT Decode / Verify
Decode JWT header and payload in the browser, then verify signatures and claims with shared secrets, PEM public keys, or JWK input.
RSA / PEM / JWK Toolbox
Generate RSA / EC keys, convert PEM and JWK material, and run compact JWS signing and verification in the browser.
File AES Encrypt / Decrypt
Encrypt and decrypt local files in the browser with AES-GCM, using passphrase-derived keys or raw keys, and export a recoverable binary package.
Certificate / CSR / Public Key Viewer
Inspect x509 certificates, CSRs, and PEM public keys in the browser, including subject, issuer, validity, SAN, fingerprints, and common extensions.
HMAC / Webhook Signature Verifier
Generate HMAC signatures in the browser and verify GitHub, Stripe, Slack, or generic webhook signature headers.
Certificate Chain / TLS Checker
Check certificate-chain order, signature relationships, validity windows, CA constraints, and TLS hostname matching in the browser.
Remote TLS Report
Connect to a remote site to inspect TLS handshake details, certificate chains, protocol, cipher, hostname checks, and the PEM bundle.
Tianzige Copybook
Generate printable tianzige handwriting sheets with selectable fonts, pinyin, and stroke-order hints.
Encoding Workbench
Encode and decode Base64, URL, HTML Entity, and Unicode text directly in the browser.
QR Code Generate and Decode Workbench
Generate QR code PNG files and decode QR text from local images directly in the browser.
Image Format Converter
Convert image formats, resize dimensions, and tune export quality directly in the browser.
Barcode Generate and Decode Workbench
Generate common 1D barcodes and decode barcode content from local images directly in the browser.
Browser OCR Tool
Run OCR locally in the browser for screenshots, scans, and image-to-text extraction.
Regex Tester
Test regular-expression matches, inspect capture groups, and preview replacements directly in the browser.
Image Editor Workbench
Crop, rotate, flip, adjust, and export images directly in the browser.
Timestamp Converter
Two-way instant conversion between Unix seconds/milliseconds and date strings.
Cron Expression Parser
Parse cron expressions in the browser, generate natural-language descriptions, and preview upcoming run times.
Diff / Patch Text Compare
Compare two text blocks, generate unified diffs, and apply patches back to the base text.
Date Time Toolkit
Handle timestamps, timezone conversions, date differences, and world-clock meeting planning with working-hour guidance directly in the browser.
Calendar Toolkit
A local monthly calendar tool that shows Gregorian dates, lunar dates, workdays, rest days, makeup workdays, and holidays.
Whiteboard Blackboard Pad
A browser whiteboard tool with handwriting, erasing, selection, undo and redo, and fullscreen presentation.
Compression Lab
Try gzip, brotli, and zstd compression and decompression directly in the browser.
URL Workbench
Inspect full URLs, review query params, and rebuild links from base, path, query, and hash.
CSV JSON Workbench
Convert between CSV and JSON with delimiter control, header modes, and read-only result preview.
Config Workbench
Convert configuration payloads between JSON, YAML, TOML, INI, and Properties.
WebSocket Test Tool
Test WebSocket connections in the browser, send messages, inspect traffic logs, and review ws/wss browser constraints.
P2P Chat Room
Create a temporary room for up to six members, chat together, and send files to everyone currently online.
Subtitle Toolkit
Process SRT, WebVTT, and ASS subtitles in the browser with format conversion, timeline shifting, and structured previews.
ffprobe Media Inspector
Inspect local audio and video files in the browser with ffprobe, including container, duration, bitrate, and stream metadata, without uploading them.