Summa: Notepad Calculator
Everyone
info
1+
Downloads
About this app
Summa is a sheet of paper that does the math. Write a line in plain words and the answer appears next to it, on the right. Change a number and everything that depends on it updates.
Words around numbers are fine
Lunch: $12 + 15% tip
Flights: 2 × €149
Hotel: 3 nights × $165 in EUR
Summa skips the words it doesn't know and works out the rest.
Units and money
5 km in miles, 72 °F in °C, 1,200 sq ft in m², 6.4 L/100 km in mpg, $25/hour × 14 hours. Live exchange rates for 166 currencies and metals, refreshed at most twice a day, with rates built in for offline use. Crypto prices if you turn them on.
Percentages, every way
20% of $10, 5% on $30, 6% off €40, $50 as a % of $100, 20 is 10% of what.
Dates, times and time zones
days until Dec 25, next friday + 2 weeks, 8:30 am + 3 h 20 min, 3 pm Munich in Tokyo, workdays until Dec 18, next holiday. Over 6,000 cities and the usual abbreviations, all offline. Workday math skips the public holidays of your region (22 countries).
Money over time
$10,000 at 5% for 10 years compounded monthly, loan of $300k at 6% for 30 years (the monthly payment), €1,350 incl 19% VAT, €120 without 20% VAT.
Your own names, units and functions
rate = $85/hour, then 6.5 hours × rate. Refer to a line with line6, the line above with prev, and add up a block with sum. Define 1 coffee = $4.50 or tip(bill) = bill × 18% once on the Definitions sheet and use them in every sheet.
Quiet by design
Just the sheet: text on the left, answers on the right, nothing floating over it. Click an answer to copy it; right-click it to copy the line or convert it. Suggestions appear as gray text after the cursor; Tab takes one.
Made for laptops, at home on phones
On Android laptops and in desktop windows your sheets are listed on the left, with keyboard shortcuts for everything. A mini calculator can stay on top of your other windows. Select a sum in any app and choose Calculate to see the answer right there. Export a sheet as PDF, a web page, CSV, Markdown or text, or print it.
Private
No accounts, no ads, no analytics. Your sheets stay on your device. The only thing Summa downloads is public exchange-rate tables, and it never sends anything about you or your sheets.
Free and open source
Summa is a personal hobby project, not affiliated with or endorsed by any employer. The code is MIT-licensed: github.com/kuscher/summa
Words around numbers are fine
Lunch: $12 + 15% tip
Flights: 2 × €149
Hotel: 3 nights × $165 in EUR
Summa skips the words it doesn't know and works out the rest.
Units and money
5 km in miles, 72 °F in °C, 1,200 sq ft in m², 6.4 L/100 km in mpg, $25/hour × 14 hours. Live exchange rates for 166 currencies and metals, refreshed at most twice a day, with rates built in for offline use. Crypto prices if you turn them on.
Percentages, every way
20% of $10, 5% on $30, 6% off €40, $50 as a % of $100, 20 is 10% of what.
Dates, times and time zones
days until Dec 25, next friday + 2 weeks, 8:30 am + 3 h 20 min, 3 pm Munich in Tokyo, workdays until Dec 18, next holiday. Over 6,000 cities and the usual abbreviations, all offline. Workday math skips the public holidays of your region (22 countries).
Money over time
$10,000 at 5% for 10 years compounded monthly, loan of $300k at 6% for 30 years (the monthly payment), €1,350 incl 19% VAT, €120 without 20% VAT.
Your own names, units and functions
rate = $85/hour, then 6.5 hours × rate. Refer to a line with line6, the line above with prev, and add up a block with sum. Define 1 coffee = $4.50 or tip(bill) = bill × 18% once on the Definitions sheet and use them in every sheet.
Quiet by design
Just the sheet: text on the left, answers on the right, nothing floating over it. Click an answer to copy it; right-click it to copy the line or convert it. Suggestions appear as gray text after the cursor; Tab takes one.
Made for laptops, at home on phones
On Android laptops and in desktop windows your sheets are listed on the left, with keyboard shortcuts for everything. A mini calculator can stay on top of your other windows. Select a sum in any app and choose Calculate to see the answer right there. Export a sheet as PDF, a web page, CSV, Markdown or text, or print it.
Private
No accounts, no ads, no analytics. Your sheets stay on your device. The only thing Summa downloads is public exchange-rate tables, and it never sends anything about you or your sheets.
Free and open source
Summa is a personal hobby project, not affiliated with or endorsed by any employer. The code is MIT-licensed: github.com/kuscher/summa
Type math the way you'd say it: units, money, dates and time zones.
Updated on
Safety starts with understanding how developers collect and share your data. Data privacy and security practices may vary based on your use, region, and age. The developer provided this information and may update it over time.
- No data shared with third partiesLearn more about how developers declare sharing
- No data collectedLearn more about how developers declare collection
What’s new
A small wording change at the bottom of Settings. Nothing else changed.
App support
About the developer
Alexander Friedrich Kuscher
kuscher.projects@gmail.com
United States
