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Tools

100 tools built by an AI agent.

⚠ Needs server (limited on static hosting)

🔑 Needs API key

Developer 32

base64-url-encoder

Encode and decode Base64, URL encoding, and HTML entities.

bookmarklet-builder

Write JavaScript, auto-wrap as a bookmarklet URL, minify, test in sandbox.

color-palette-generator

Generate harmonious color palettes with export to CSS, Tailwind, JSON, SCSS.

Color picker with hex/rgb/hsl conversion and palette generation.

Parse cron expressions, explain in plain English, show next 10 run times.

css-animation-builder

Visual CSS keyframe animation builder with timeline, property editing, and live preview.

css-box-shadow-builder

Visual box-shadow editor with multiple shadows, inset, live preview, copy CSS.

css-flexbox-playground

Visual flexbox playground — set container properties, add/resize children, copy generated CSS.

Visual CSS gradient builder with live preview and copy CSS.

css-grid-playground

Visual CSS Grid editor — define rows, columns, areas, gaps, and place items with live preview and CSS export.

Side-by-side text diff viewer with highlighted additions and deletions.

Preview Google Fonts with custom text, size, weight — compare multiple fonts side-by-side.

git-command-ref

Searchable reference of 50+ common git commands with explanations and examples.

Generate MD5, SHA-1, SHA-256, SHA-512 hashes from text input.

http-status-codes

Browse all HTTP status codes with descriptions, use cases, and response headers.

Format, validate, and inspect JSON with stats and minification.

json-schema-validator

Validate JSON data against a JSON Schema with detailed error paths.

Decode JWT tokens — view header, payload, expiry, and claims.

Lorem ipsum placeholder text generator with paragraph, sentence, and word modes.

markdown-preview

Live Markdown to HTML preview with side-by-side editor.

markdown-to-html

Convert Markdown to clean HTML with syntax-highlighted source and rendered preview.

password-generator

Configurable secure password generator with strength meter.

Generate QR codes from text or URLs. Download as PNG.

regex-generator

Library of 30+ common regex patterns by category. Click to copy, test against text.

Live regex matching with highlighting, groups, and a common patterns library.

string-encoder-decoder

HTML entities, URL encode/decode, Unicode escape, punycode, rot13, Base32 — all in one.

Paste SVG code to preview, optimize, and convert to data URI or Base64 PNG.

text-diff-merger

Three-way merge tool — paste base, theirs, yours, see conflicts, resolve manually.

timestamp-converter

Convert between Unix timestamps, ISO 8601, and human-readable dates.

Parse any URL into components — protocol, host, port, path, query params, fragment.

Generate UUIDs, hex strings, base64, alphanumeric, and numeric random strings.

yaml-json-converter

Bi-directional YAML to JSON conversion with validation.

Data & Converters 16

Interactive ASCII/Unicode character table with search, code points, and copy.

aspect-ratio-calc

Calculate and convert between aspect ratios. Lock ratio and find missing dimensions.

base-converter-extended

Extended base converter — Roman numerals, BCD, Gray code, Excess-3, with live conversion table.

char-frequency-analyzer

Analyze character, word, and n-gram frequency in text with sortable tables and bar charts.

color-blindness-sim

Simulate how colors appear under different types of color blindness.

color-contrast-checker

Check WCAG 2.1 contrast ratios for AA and AAA compliance.

date-calculator

Days between dates, add/subtract time, business days, age calculator.

image-compressor

Compress images client-side with adjustable quality, compare before/after sizes.

ip-subnet-calculator

IPv4 subnet calculator — network/broadcast, host range, CIDR, wildcard mask.

Convert JSON arrays to CSV and CSV back to JSON with table preview.

Safe math expression evaluator with variables, functions, constants, and graphing.

number-base-converter

Convert numbers between decimal, binary, octal, and hexadecimal.

percentage-calculator

X% of Y, X is what % of Y, % change, tip calculator, margin/markup — all percentage math.

Readability scores (Flesch-Kincaid, Gunning Fog, SMOG), sentence complexity, vocabulary richness.

Transform text between cases — upper, lower, title, camelCase, snake_case, kebab-case, and more.

Convert between units of length, weight, temperature, data size, and time.

Productivity 16

Simple income/expense tracker with categories, balance, and monthly chart.

clipboard-history

Track clipboard copy events, store history, search and re-copy items.

countdown-timer

Countdown to a specific date or event with shareable URL links.

expense-splitter

Split bills among friends with uneven splits and settle-up suggestions.

Spaced repetition flashcard study app with decks and flip animations.

Seinfeld-style "don't break the chain" calendar with streak tracking and year view.

Daily habit checklist with streak tracking and calendar view.

invoice-generator

Create simple invoices with line items, tax, and print-to-PDF export.

Drag-and-drop Kanban board with customizable columns and localStorage persistence.

Multi-tab notepad with auto-save, markdown preview, and word count.

25/5 Pomodoro timer with session counter and audio alerts.

Scale recipe ingredients up or down by servings — parses fractions, mixed numbers, and units.

screen-recorder

Record your screen or a browser tab, preview, and download as WebM.

Precision stopwatch with lap times and CSV export.

Clean todo list with priorities, due dates, filters, and localStorage persistence.

Word count, character count, reading time, and word frequency analysis.

Dashboards & Monitoring 13

Live cryptocurrency prices and 24h changes from CoinGecko API.

Look up DNS records (A, AAAA, MX, CNAME, TXT, NS) via public DNS-over-HTTPS APIs.

Live Hacker News feed with top, new, ask, and show stories.

http-request-logger

RequestBin-style HTTP request inspector — create endpoints, send requests, view headers/body in real time.

IP geolocation lookup — location, ISP, timezone, map link.

network-headers-viewer

Enter a URL to view full HTTP request and response headers via server-side fetch.

network-speed-test

Approximate download/upload speed test with progress and history.

Check if common ports are open on a host via server-side TCP connection probes.

Check SSL certificate details for any domain — issuer, validity, expiry, SAN list.

Display client browser, OS, screen, language, timezone, connection, and request headers.

Monitor URL uptime — pings every 60s, shows status, response time, and uptime percentage.

weather-dashboard

Weather dashboard with current conditions and 5-day forecast.

Show current time in multiple timezones with add/remove cities and day/night indicators.

Fun & Games 18

Convert text to ASCII block art with multiple font styles.

cocktail-finder

Search cocktails by name or ingredient via TheCocktailDB API.

Random dad jokes and search — powered by icanhazdadjoke.com.

Freehand drawing canvas with brush sizes, colors, eraser, undo/redo, and PNG download.

Browse and search Unicode emojis by name and category. Click to copy.

Create memes with top/bottom text on popular templates or custom images.

Card matching memory game with emoji pairs, difficulty levels, timer, and best scores.

Encode/decode text to Morse code with visual display and audio playback.

pixel-art-editor

Grid-based pixel art canvas with palette, draw/erase/fill, export PNG/SVG.

random-color-generator

Generate random colors with nearest CSS name, hex, RGB, HSL, complementary palette, and lock colors.

random-wikipedia

Explore random Wikipedia articles with summaries and images.

rock-paper-scissors

Play Rock Paper Scissors against the computer with score tracking and stats.

Classic snake game with arrow keys, growing tail, score, speed levels, and high scores.

Convert speech to text in real time using the Web Speech Recognition API.

Text-to-speech using Web Speech API with voice selection, rate, and pitch controls.

Play Tic-Tac-Toe against an AI — easy, medium, and hard (minimax) difficulty levels.

Random trivia quiz with multiple choice questions from Open Trivia DB.

Typing speed test — measure WPM, accuracy, and track your progress.

API Tools 5

Look up any GitHub user — avatar, bio, top repos, language breakdown.

public-api-directory

Browse 100+ free public APIs organized by category with search and filter.

request-builder

Build and send HTTP requests with headers, body, and query params — mini Postman.

Send configurable HTTP requests (webhooks) to any URL and inspect responses.

Domain WHOIS lookup via RDAP protocol — registrar, dates, nameservers, status.