Everyday tools that run in your browser

Name Wheel

Spin the wheel to pick a random person.

Random Picker

Fast random picks with no-repeat mode.

Group Maker

Random groups, then swap to fine-tune.

Timer & Stopwatch

Countdown presets and lap timing.

Pomodoro Timer

Focus sprints with a task list and background noise.

Scoreboard

Team points with a built-in game clock.

Noise Meter

Show the class when it gets too loud.

QR Generator

Make QR codes for links and Wi-Fi.

Bracket

Single-elimination tournament bracket.

Interval Timer

Work and rest rounds for drills.

Agenda Timer

One countdown per meeting item.

Seating Chart

Auto-seat tables and print.

Dice & Coin

D4 to D100 plus a coin flip.

Background Remover

Remove backgrounds in-browser, transparent PNG.

Image to Text (OCR)

Extract text from images in-browser.

AI Image Upscaler 2×

Double image size in-browser with AI.

Image Compressor

Reduce JPG, PNG and WebP file size by quality or an exact target — in batches.

Image Resizer

Resize one photo or a whole batch by pixels, percentage or a longest-edge limit.

Image Converter

Convert photos between JPG, PNG and WebP — one file or a whole batch.

HEIC to JPG Converter

Turn iPhone HEIC/HEIF photos into JPG or PNG — in batches, right on your device.

Crop Image

Crop, rotate and flip with precision — export JPG or PNG in one click.

Favicon Generator

One square image in — favicon.ico, Apple touch icon and PNGs out.

Image Watermark

Stamp text or a logo onto a whole batch of photos — locally, never uploaded.

EXIF Remover

Inspect and erase camera info, dates and GPS locations from photos.

Image to PDF

Combine multiple photos into a single PDF — in your chosen page size and order.

Social Media Image Resizer

One photo, every platform size — pick what you need and export a ZIP.

Color Palette Extractor

Pull the dominant colors out of any photo — or pick exact pixels yourself.

Percentage Calculator

Calculate percentages, percentage increase and change instantly in your browser.

Age Calculator

Find exact age in years, months and days between any two dates.

Date Duration Calculator

Count days, weeks, months and hours between two dates.

Discount & Sale Price Calculator

Work out sale price, double discounts and savings in seconds.

Tip Calculator & Bill Splitter

Calculate the tip and split a bill evenly among any number of people.

Unit Price Calculator

Compare price per unit between packages and see which one is cheaper.

BMI Calculator (with BMR & TDEE)

Calculate BMI, healthy weight range, basal metabolism and daily calorie needs.

Loan & Amortization Calculator

Monthly payment, total interest and full amortization schedule for any loan.

Compound Interest Calculator

Project savings growth with regular contributions and any compounding frequency.

Final Grade Calculator

See the score you need on a final exam to reach your target grade.

GPA Calculator

Add courses, letter grades and credits to calculate your GPA on a 4.0 scale.

Fuel Cost Calculator

Estimate trip fuel cost in L/100 km or MPG, with round-trip option.

Salary Converter

Convert hourly, weekly, monthly and yearly pay at any working-hours schedule.

Sales Tax Calculator

Add or reverse sales tax and get the total price including tax.

Random Number Generator

Generate cryptographically secure random numbers, with or without repeats.

Currency Converter

Convert between world currencies with daily mid-market rates; works offline with a bundled snapshot.

Unit Converter

Convert length, weight, temperature, area, volume, speed and more — free and offline.

Length Converter

Convert meters, feet, inches, kilometers, miles, nautical miles and Chinese units.

Weight Converter

Convert kilograms, pounds, ounces, grams, stones, tons and jin.

Temperature Converter

Convert Celsius, Fahrenheit and Kelvin instantly.

Area Converter

Square meters, feet, acres, hectares, square miles and mu in one converter.

Volume Converter

Liters, gallons, quarts, cups, fluid ounces and cubic meters.

Speed Converter

Kilometers per hour, miles per hour, knots, meters per second and more.

Data Storage Converter

Convert bytes, KB/MB/GB/TB and binary KiB/MiB/GiB/TiB units accurately.

Number Base Converter

Convert numbers between binary, octal, decimal and hexadecimal, or any base 2–36.

Roman Numeral Converter

Convert numbers to Roman numerals and back — years, dates and clock faces.

Shoe Size Converter

Convert shoe sizes across EU, US, UK and CN systems for men, women and kids.

Ring Size Converter

Turn finger circumference or diameter into US, EU, CN and JP ring sizes.

Cooking Measurement Converter

Cups, tablespoons, teaspoons, grams and milliliters with ingredient densities.

Unix Timestamp Converter

Convert Unix epoch seconds or milliseconds to human dates and back, in UTC and local time.

World Clock & Meeting Planner

Live clocks for any time zone and find the best overlap hour for cross-time-zone meetings.

Color Converter

Convert colors between HEX, RGB, HSL and CMYK with one click and copy any value.

Pixel & Print Size Converter

Convert px, pt and rem, plus inches/cm to pixels at any DPI for print and web.

Merge PDF Files

Combine multiple PDFs in any order into one file. Everything stays on your device.

Split PDF

Extract page ranges or split every N pages into separate PDFs downloaded as a ZIP.

Rotate, Delete & Reorder PDF Pages

Rotate pages 90°, remove pages and drag-free reorder them with live thumbnails.

PDF to Text Converter

Extract selectable text from a PDF and copy or download it as a TXT file.

PDF to Images Converter

Export every PDF page as high-quality PNG or JPG images in a ZIP archive.

Compress PDF

Shrink PDFs with lossless repacking or strong image recompression, fully on your device.

Add Page Numbers to PDF

Stamp page numbers in any corner, with custom format, start number and font size.

Case Converter

UPPER, lower, Title, sentence, camel, snake, kebab and alternating case in one click.

Word Counter

Count words, characters, sentences, paragraphs and estimate reading time as you type.

Text Diff Checker

Compare two texts and highlight every added or removed line instantly.

Sort & Deduplicate Lines

Sort lines alphabetically, remove duplicates, trim spaces and delete blank lines.

Number to Words Converter

Spell numbers in English or convert amounts to Chinese financial capital characters.

URL Slug Generator

Turn any title into a clean, SEO-friendly URL slug with your chosen separator.

JSON Formatter & Validator

Beautify, validate and minify JSON with clear error positions — all in your browser.

JSON to CSV / CSV to JSON

Convert JSON arrays to spreadsheets-ready CSV and back, including nested fields.

XML Formatter

Beautify and indent XML/SVG/HTML documents and validate well-formedness instantly.

YAML to JSON Converter

Convert YAML config files to JSON and back, with validation and error messages.

Markdown to HTML Converter

Write Markdown and instantly preview the rendered HTML, then copy the source.

SQL Formatter

Beautify and indent SQL queries with optional keyword uppercasing.

URL Encode / Decode

Percent-encode or decode URLs and query parameters safely and instantly.

Base64 Encode / Decode

Encode text and files as Base64 or decode data URLs — supports Unicode and images.

JWT Decoder

Decode JWT header and payload, inspect claims and expiry — tokens are never sent anywhere.

SHA Hash Generator

Generate SHA-1, SHA-256, SHA-384 and SHA-512 hashes from text with the Web Crypto API.

UUID Generator

Generate one or thousands of RFC-4122 v4 UUIDs instantly, with optional braces and uppercase.

Password Generator & Strength Meter

Create strong random passwords locally and measure their entropy in bits.

File Checksum Calculator

Calculate SHA-1/256/384/512 checksums of any file locally and compare against an expected hash.

CSV to Excel Converter

Turn CSV files into formatted .xlsx spreadsheets in your browser — no upload, no sign-up.

vCard Generator

Create a digital contact card (.vcf) ready to save on a phone or share by QR code.

Barcode Generator

Create CODE128, EAN-13, UPC, CODE39 and ITF barcodes as PNG or SVG, free.

Lorem Ipsum Generator

Generate placeholder paragraphs, sentences or words for mockups and designs.

SVG Minifier

Strip comments and redundant whitespace from SVG markup and download the smaller file.

SVG to React Converter

Turn raw SVG into a ready-to-paste React JSX component with camelCased attributes.

Image to Base64 Converter

Convert images to data URLs with ready CSS background and HTML snippets to copy.

Color Contrast Checker (WCAG)

Check text contrast ratios against WCAG 2.1 AA and AAA standards.

Cron Expression Explainer

Translate 5-field cron schedules into plain English and preview the next run times.

Device & Screen Tester

Show screen specs and run dead-pixel, keyboard, microphone and camera tests.

Classroom Traffic Light

Show red, yellow or green full screen for noise control — click, tap or use number keys.

LED Scrolling Banner

Turn your screen into a full-screen scrolling LED sign for sports day and events.

Name Place Cards

Paste a class list and print foldable name tent cards in three sizes.

Countdown Poster

Project a giant full-screen countdown to exams, holidays or any event date.

Random Order Generator

Shuffle a name list into a random presentation or line-up order and reveal one by one.

Bingo Card Generator

Print a set of shuffled 5×5 bingo cards with your own word list for class review games.

China Income Tax Calculator (IIT)

Estimate annual individual income tax with the seven-bracket progressive table, social insurance and special deductions.

Timesheet & Overtime Pay Calculator

Add regular and overtime hours at 1.5x, 2x or 3x multipliers to get weekly or monthly gross pay.

Workday Calculator

Add or subtract business days skipping weekends, or count working days between two dates.

Gross Margin Calculator

Calculate gross profit, gross margin percentage and markup from cost and revenue.

Break-Even Calculator

Find the units and revenue needed to cover fixed and variable costs, with contribution margin.

Sales Commission Calculator

Work out commission at any rate plus base salary and total monthly earnings.

Depreciation Calculator

Straight-line and double-declining-balance depreciation schedule with book value.

Sample Size Calculator

Get the required survey sample size for 90/95/99% confidence, margin of error and population size.

Electricity Cost Calculator

Estimate kWh usage and running cost of any appliance per day, month and year.

Sleep Cycle Calculator

Plan bedtimes or wake times around 90-minute sleep cycles to wake up rested.

Pregnancy Due Date Calculator

Estimate due date, conception date, current gestational week and trimester boundaries from LMP.

Body Fat Calculator (US Navy)

Estimate body fat percentage with the U.S. Navy tape method and see fat and lean mass.

Ohm's Law Calculator

Solve voltage, current or resistance and calculate power with the P = V·I triangle.

Rental Yield Calculator

Calculate gross and net rental yield, annual rent and expenses for a property.

Product Profit Calculator

Set a sale price against cost, shipping and platform fees to see profit, margin and ROI.

Volumetric Weight Calculator

Compare dimensional weight with actual weight using 5000, 6000, 7000 or 139 divisors.

Resistor Color Code Calculator

Read four-band resistor colors into ohms, multiplier and tolerance range.

Fraction Calculator

Add, subtract, multiply and divide fractions, automatically simplified with decimal result.

Statistics Calculator

Paste a data set to get mean, median, mode, range, variance and standard deviation.

GCD & LCM Calculator

Enter integers to get the greatest common divisor, least common multiple and prime factors.

Combination & Permutation Calculator

Enter n and r to compute nCr combinations, nPr permutations and factorials.

Subnet Calculator (CIDR)

Parse an IP/CIDR into network address, netmask, broadcast, host range and host count.

NPV & IRR Calculator

Enter a discount rate on the first line and cash flows below to compute NPV and IRR.

JSON to TypeScript Converter

Turn sample JSON into typed TypeScript interfaces instantly in your browser.

Text Redactor & Data Masker

Mask phone numbers, emails, Chinese ID cards and bank card numbers before sharing text.

URL Parser & Query Expander

Break URLs into protocol, host, port, path and every query parameter, one per line.

User-Agent Parser

Detect browser, engine, operating system and device type from a User-Agent string.

HTML Entities Encoder/Decoder

Encode text to HTML entities and decode entities back, with named or numeric output.

CSS Minifier

Strip comments, whitespace and redundant semicolons from CSS entirely in your browser.

Morse Code Translator

Translate text to International Morse code and decode Morse back to text, offline.

Keyword Density Analyzer

Count word frequencies and density percentages in your content, with the top terms ranked.

Readability Checker

Score English text with Flesch Reading Ease and grade-level formulas, plus sentence stats.

robots.txt Generator

Generate allow-all, block-all or custom robots.txt rules with an optional sitemap line.

Gold & Precious Metal Weight Converter

Convert grams, Chinese liang and qian, Hong Kong tael, troy ounces and carats.