Free smart calculator that works like math notes. Variables, live exchange rates, unit conversions, percentages, and date. — all in one. No ads. No account needed.

A smart calculator that works like math notes.

Just type "price = 12000" and you're done. Calto is a free smart calculator that lets you write naturally like a math notepad while showing results in real-time.

Why Calto?

Regular calculators just show numbers. But real-life calculations are more complex.

• Planning a trip budget and splitting expenses
• Converting currencies while budgeting
• Calculating tips, discounts, or freelance rates

Calto handles all of this naturally, like taking notes.

Key Features

Variables

coffee = 4.50 lunch = 12.00 coffee + lunch = 16.50

Name your numbers. Make calculations meaningful.

Exponent Calculations

2^10 = 1,024 3^3 = 27

Power calculations in one line.

Natural Unit Conversion

10km in mile = 6.21 25C in F = 77 500g in oz = 17.64 100m2 in acre = 0.025

80+ units supported. Length, weight, volume, temperature, time, area, angle.

Live Exchange Rates

100 USD in EUR = 92.50 50 GBP in JPY = 9,375

6 major currencies. Auto-updated every 24 hours.

Mixed Currency Math

100 USD + 50 EUR = $154.25

Different currencies in one calculation. Just works.

Date Calculations

today + 30days = 2026-03-04 today + 2weeks = 2026-02-16

Project deadlines, travel dates made easy.

Percent & Tip Calculator

20% of 5000 = 1,000 15% tip on 85 = 12.75

Discounts, tips, split bills. Type what you think.

Crypto Calculator

1 BTC in USD = 97,500 0.5 ETH in EUR = 1,650

Live cryptocurrency rates. Track your crypto portfolio.

Perfect For

• Trip budgeting and expense tracking
• Freelancers calculating rates and invoices
• Quick tip calculator and bill splitter
• Real-time exchange rate conversions
• Anyone tired of basic calculators

Privacy First - Offline Calculator

• All calculations stored on device only
• Works offline - no internet required for basic math
• Only anonymized usage statistics collected (for service improvement)
• No account required

Support

Email: iamjw.dev@gmail.com Website: https://calto.iamjw.kr

Download this free calculator now and experience math notes done right.