Converters & Calculators
Convert units, currencies, and time zones. Calculate tips, ages, and recipes.
Unit, currency, and time zone conversions, along with everyday calculations like tips and recipe scaling, are things almost everyone needs occasionally and almost nobody wants to do by hand. This category groups those small, frequent conversions together specifically because they're too minor individually to search for a dedicated app, but genuinely useful to have on hand as a set.
HEIC to JPG Converter
Turn iPhone HEIC photos into JPG, PNG, WebP or PDF in your browser. Nothing is uploaded.
Unit Converter
Convert length, weight, temperature, and more
Currency Converter
Convert currencies with the latest daily exchange rates
Time Zone Converter
Convert times between any time zones, and see your event agenda in each zone
Tip Calculator
Calculate tips and split bills easily
Business Days Calculator
Count working days between two dates or add working days to find a deadline, with your own weekend and holidays
Online Timer
Countdown timer with 1, 5, 10 and 20 minute presets, a custom time, a Pomodoro mode and a floating pop-out view
Age & Date Calculator
Calculate age, date differences, and more
Job Experience Calculator
Calculate work experience in years, months, and days — add multiple jobs for a combined total
Recipe Scaler
Scale recipe ingredients up or down
Percentage Calculator
Calculate percentages, percentage change, and what-percent-of
GPA Calculator
Calculate your grade point average from courses and credits
Roman Numeral Converter
Convert between numbers and Roman numerals
Random Number Generator
Generate random numbers in any range, with or without duplicates
Final Grade Calculator
Find the score you need on your final exam to finish the course with the grade you want
Book Spine and Cover Size Calculator
Estimate spine width and full wrap-cover size with bleed for KDP, IngramSpark and Lulu, with a to-scale layout preview.
Print Cost and Royalty Calculator
Work out the printing cost of a paperback, what you earn per copy at a list price, the price for a target royalty and the copies needed to earn back your costs.