Developer Tools
Tool Count: 23Covers JSON, regex, URL, and Markdown workflows for everyday development and data cleanup tasks.
Professional Calculators With Practical Context
Tools are organized by real-world scenarios with consistent input and output conventions.
Total Tools97
LanguagesEN / ZH
ExperienceUnified Flow
Usage Standards
- Tools are ordered for practical task discovery.
- Outputs are transparent and easier to verify.
- Logic is maintained continuously for reliability.
Tool Category Guide
Inspired by broad utility-site navigation patterns, the library is grouped into clear scenario-based categories so users can find the right tool faster.
Security Tools
Tool Count: 13Focused on signing, hashing, password, and token inspection for practical security verification.
Text Tools
Tool Count: 12Groups compare, count, case conversion, and abbreviation utilities for fast text operations.
Conversion Tools
Tool Count: 8Brings unit, timezone, full-width, Roman numeral, and lunar date conversions into one place.
Life Utilities
Tool Count: 34Combines BMI, date, giveaway, finance, travel, and parenting tasks for frequent daily use.
Image Utilities
Tool Count: 7Supports QR generation, paper size lookup, and lightweight visual output tasks.
All Calculators
JSON Formatter
Format, minify, and validate JSON content.
Base64 Encoder/Decoder
Convert text and Base64 content both ways.
SHA-256 Hash Generator
Generate SHA-256 hashes instantly.
Timestamp Converter
Convert Unix timestamps and date time values.
Regex Tester
Test regular expression matches in real time.
URL Encoder/Decoder
Encode and decode URL strings quickly.
Random Generator
Generate random numbers, strings, and color codes.
Text Diff Checker
Compare two texts and inspect line-level changes.
Password Strength Checker
Evaluate password strength quickly.
QR Code Generator
Generate QR codes instantly from your input.
Password Generator
Generate strong random passwords with custom options.
JWT Parser
Parse JWT header, payload, and signature.
HMAC Generator
Generate HMAC-SHA256 signatures.
Word Counter
Count characters, words, and lines.
Case Converter
Convert text into common naming and case formats.
Markdown Editor
Edit and preview markdown content instantly.
Scientific Calculator
Evaluate expressions with common math functions.
Countdown Timer
Set a target date and track time remaining.
Combined Unit Converter
Convert length, volume, mass, temperature, and more.
Age Calculator
Calculate age based on birth date.
Future Time Calculator
Add days and time to a date.
Temperature Converter
Convert temperature units quickly.
Cat Age Calculator
Convert cat years to human years.
Dog Age Calculator
Convert dog years to human years.
BMI Calculator
Estimate body mass index and range.
Female Body Ratio
Estimate bust, waist, hip by height.
Energy & Calorie Converter
Convert energy and calorie units.
Length Converter
Convert length units quickly.
Power Converter
Convert power units.
Pressure Converter
Convert pressure units.
Volume Converter
Convert volume and capacity.
Mass Converter
Convert mass and weight units.
Area Converter
Convert area units.
Resistor Color Code
Resistor band reference table.
Paper & Photo Sizes
Common paper and photo dimensions.
Multiplication Table
9x9 and extended tables.
Kinship Title Calculator
Build a relationship path to get the title.
Loan Payment
Calculate monthly payment by rate and term.
Mortgage Estimator
Estimate mortgage payment and interest.
Percentage
Compute ratios and growth quickly.
Date Difference
Find day difference between dates.
Speed Unit Converter
Convert km/h, mph, m/s, knots and more.
Full-width / Half-width Converter
Convert letters, numbers, and punctuation between full and half width.
Roman Numeral Converter
Convert between Arabic and Roman numerals.
Stopwatch
Time laps and record each split.
Random Picker / Raffle
Enter options and randomly pick one or more for raffles and decisions.
Daily Calorie Calculator
Estimate daily calorie needs from weight, height, age, and activity.
World Time / Timezone Converter
View local time across timezones in real time.
HTML Entities Encoder/Decoder
Convert text and HTML entity characters both ways.
Simple Counter
Count up or down for headcount, traffic control, and more.
Color Picker & Converter
Convert between HEX and RGB with live preview.
AC Unit Converter
Convert kW, BTU/h, kcal/h, and tons for cooling capacity.
Shoe Size Converter
Convert EU, US, and foot length (cm).
BaZi Weight Calculator
Look up birth weight and fortune from lunar birth date (Chinese tradition).
Lunar / Solar Converter
Convert between Gregorian and Chinese lunar dates using lookup tables.
Chinese Zodiac Year Lookup
Enter a year to find its Chinese zodiac animal (Rat, Ox, Tiger, etc.).
Baby Milk Calculator
Estimate daily and per-feed milk volume by baby weight and age.
Taiwan Stock Trading Calculator
Calculate buy/sell amounts, fees, and tax for Taiwan stock trades.
12 Double-Hour Chart
Look up the traditional Chinese double-hour (ๅญไธๅฏ ๅฏ) from 24-hour time.
Zodiac Sign Lookup
Find your zodiac sign by birth month and day, with traits and element.
Fever Temperature Chart
Check if temperature is normal, low fever, or fever (Celsius/Fahrenheit).
Qinggong Gender Chart
Traditional folklore predictor for baby gender by lunar month and virtual age.
Date Countdown
Count down to important dates: discharge, birthday, exam, wedding. Live countdown.
Country Code Lookup
Quick lookup of country codes: Chinese, English, ISO alpha-2/3, numeric.
Slot Machine Raffle
Raffle, gift exchange, lottery. Custom digit count and range, spin to draw.
Date Calculator
Find the date N days later or earlier from any start date.
Current Clock
Display current time, date, day of week. Timezone auto-detected.
English Abbreviations
Lookup common abbreviations: months, buildings, streets, directions, etc.
Travel Checklist
Essential packing checklist: documents, clothes, daily items, electronics. Check off and save.
LED Marquee
Custom text, colors, speed, font size. Turn your device into a scrolling marquee sign.
Special Emoticons
Smileys, hearts, arrows, zodiac. Click to copy.
Baby Essentials Checklist
Baby items, breastfeeding, cleaning, bath, outdoor. Check off and save.
Taiwan Stock Profit Calculator
Estimate profit, fees, and transaction tax from buy price, sell price, and shares.
Baby Birth Days Calculator
Calculate total days, weeks, and calendar age since birth.
AC Room Size Calculator
Estimate cooling capacity from room area and sunlight conditions.
Zhuyin Keyboard Decoder
Convert mistyped Latin keyboard input back into Bopomofo symbols.
Handwritten Signature Generator
Draw a signature on canvas and export it as a PNG image.
Fancy Text Generator
Create bold, circled, fullwidth, and other stylized text variants quickly.
Birthday Emoticon Generator
Generate ready-to-copy birthday symbol messages with a name and greeting.
IP Lookup Tool
Check your current public IP, region, timezone, and network provider info.
QR Code Scanner
Decode QR codes from live camera input or uploaded images.
Webcam / Microphone Test
Quickly test webcam preview and microphone input level.
Text Encrypt / Decrypt Tool
Use browser-native Web Crypto for local AES-GCM text encryption and decryption.
Mojibake Recovery Tool
Try common repair paths for UTF-8, Latin-1, and Big5-style garbled text.
Text Crypto / Hash Suite
Combine SHA hashing and AES-GCM text encryption/decryption in one workflow.
Webhook / JSON Validator
Validate webhook URL, headers, and JSON body, then generate a cURL preview.
JWT Sign / Verify Tool
Sign and verify HS256 JWT tokens locally in the browser.
IP Whois / ASN Lookup
Look up ASN, organization, ISP, and region details for an IP address.
Image EXIF Inspector / Remover
Inspect image EXIF metadata and export a cleaned image without metadata.
Base64 / Hex / URL Codec Suite
Combine Base64, Hex, and URL encode/decode workflows for debugging and data conversion.
HMAC / Webhook Signature Verifier
Generate and verify HMAC-SHA256 webhook signatures in multiple formats.
HTTP Header Inspector
Paste raw HTTP headers to inspect security header coverage and formatting issues.
Image Metadata Inspector
Inspect file summary, dimensions, resolution, and EXIF / metadata in one view.
PEM / CSR / Certificate Parser
Detect PEM blocks and parse basic information from certificates, keys, and CSRs.
Currency Converter
Convert JPY, USD, EUR, GBP, KRW, HKD, CNY and TWD instantly.
LLM API Cost Calculator
Compare token costs across GPT-4o, Gemini, Claude, DeepSeek, and more.
Stock Return Calculator
Enter buy price, sell price, and holding period to calculate total and annualized return.