Free Online Tools
40+ free online tools for travel, finance, developers, marketers, and daily life. No signup required.
Travel
Handle your pre-trip checklist in one place: tax-free refund estimates, Japan IC card comparison, and voltage & plug checks by country.
Tax Free Calculator
Calculate your tax refund for Japan, Europe, Thailand and more.
IC Card Guide
Compare Suica, ICOCA, Pasmo and other Asian transit cards.
Voltage & Plug Guide
Check voltage, frequency and plug types by country.
Tip Calculator
Calculate tips and split bills for dining and travel.
Japan Address Guide
Understand Japanese address structure, prefectures, and postal codes.
Korea Train Guide
Compare KTX, SRT fares, travel times and station info.
Finance & Tax
Calculate Korean take-home pay, severance, loan interest, and acquisition tax based on current Korean tax and labor law. Every calculator cites its legal basis and official rates at the bottom of the page.
Severance Pay Calculator
Calculate Korean severance pay and tax.
Jeonse-Wolse Converter
Convert between Korean Jeonse and Wolse.
Acquisition Tax Calculator
Calculate Korean property acquisition tax.
Electricity Calculator
Calculate Korean electricity bill with progressive rates.
Annual Leave Calculator
Calculate Korean annual leave days by service years.
Weekly Holiday Pay Calculator
Calculate Korean weekly holiday pay for part-time and full-time workers.
Salary Converter
Convert between annual, monthly, weekly, daily, and hourly pay.
Loan Calculator
Calculate loan payments with amortization schedule.
Compound Interest Calculator
Calculate compound interest with monthly contributions.
Currency Converter
Convert between 20+ currencies with approximate rates.
Rent vs Buy Calculator
Compare renting vs buying a home over time.
Invoice Generator
Create and print professional invoices for free.
Income Tax Calculator
Calculate Korean income tax for freelancers.
Capital Gains Tax Calculator
Calculate Korean property capital gains tax.
4 Major Insurance Calculator
Calculate Korean social insurance premiums.
Take-Home Pay Calculator
Calculate net salary after taxes and insurance.
Utility Bill Calculator
Calculate electricity, gas, and water bills combined.
Developer
Format JSON, decode JWTs, and test regex right in your browser. Your input never leaves your device — all processing happens client-side.
Password Generator
Generate strong random passwords with strength meter.
Color Blindness Simulator
Simulate color blindness types with WCAG contrast check.
Crontab Generator
Generate and validate cron expressions with ease.
SVG to ICO Converter
Convert SVG files to multi-size ICO favicons.
OG Tag Preview
Preview Open Graph tags for social media sharing.
JSON Formatter & Validator
Format, minify, and validate JSON with tree view.
Base64 Encoder/Decoder
Encode and decode Base64 text and images.
URL Encoder/Decoder
Encode, decode URLs and parse query strings.
JWT Decoder
Decode JWT tokens, check expiration, and view claims.
Regex Tester
Test regular expressions with real-time highlighting.
Diff Checker
Compare two texts side-by-side with character-level diff.
UUID Generator
Generate UUID v4, v7, ULID with bulk and validation.
Hash Generator
Generate MD5, SHA-256, SHA-512 hashes with HMAC support.
Color Converter
Convert colors between HEX, RGB, HSL, CMYK with WCAG contrast check.
Timestamp Converter
Convert Unix timestamps to dates with timezone support.
Marketing & SEO
Practical marketing and SEO tools: UTM builder, meta tag and structured data generators, and OG tag preview — built against Google's official documentation and open standards.
UTM Builder
Build UTM campaign URLs with presets and QR codes.
Meta Tag Generator
Generate SEO meta tags, Open Graph, and Twitter Cards.
robots.txt Generator
Create and test robots.txt files with AI bot blocking.
Schema Markup Generator
Generate JSON-LD structured data for rich search results.
Sitemap Generator
Generate XML sitemaps with validation and download.
Word & Character Counter
Count words, characters, and analyze keyword density.
Lorem Ipsum Generator
Generate placeholder text in multiple styles.
Headline Analyzer
Score and optimize your headlines for SEO and engagement.
Redirect Checker
Trace HTTP redirect chains and check status codes.
Favicon Checker
Check all favicon variants and get optimization tips.
Korea
Tools built for life in Korea: age calculation under the unified age system, jeonse-wolse conversion, military discharge dates, and public holidays — kept up to date with Korean law.
Business Registration Checker
Check Korean business registration status.
Korea Map Code
Get map coordinates for Korean addresses.
Military Service Calculator
Calculate Korean military service discharge date.
Korean Holidays
Korean public holidays and bridge day planner.
Korean Name Romanizer
Convert Korean names to English with passport-style romanization.
Korean Age Calculator
Calculate Korean age, international age, and zodiac animal.
Korean Address Converter
Convert Korean addresses to English for international shipping.
Korea Visa Checker
Check visa requirements for South Korea by nationality.
Jeonse Fraud Checker
Assess jeonse fraud risk with interactive checklist.
Global
Everyday converters built on international (ISO) standards: shoe, clothing, and ring sizes, BMI, and more.
Shoe Size Converter
Convert shoe sizes between US, EU, UK, JP, KR systems.
Ring Size Converter
Convert ring sizes between US, EU, UK, JP, KR systems.
Percentage Calculator
Calculate percentages, increases, decreases, and ratios.
BMI Calculator
Calculate BMI with WHO and Asia-Pacific standards.
TDEE Calculator
Calculate daily calorie needs with BMR and activity level.
Age Calculator
Calculate exact age, zodiac, generation, and birthday countdown.
Timezone Converter
Convert times between world timezones.
Wi-Fi QR Generator
Generate QR codes for Wi-Fi network sharing.
Paper Size Comparison
Compare paper sizes: A4, Letter, Legal and more.
Clothing Size Converter
Convert clothing sizes between international systems.