Type it.
Plainsum works it out.
Plainsum is a notes app that calculates as you type. Write a first line like todo list or cal tracker and the whole page becomes that tool.
Results as you type
A calculator that reads like notes
Write the way you think. Units, money, percentages, and time zones work on any line, and the answer sits right next to it.
Pages with a type
Two words turn a page into a tool
Type todo list and your times start counting down. Type cal tracker and every food you write shows its calories.
Short forms
Abbreviations that know where they are
On a recipe, c means cup. On a converter, c means Celsius. The page decides, so you can type the short version everywhere.
Connected pages
Your pages share their numbers
Type connect on a grocery list and pick your budget. Then a line that says groceries on the budget adds up the whole list. Workouts and steps subtract from your calories the same way.
Charts
Type chart, get a chart
Under a calorie tracker it graphs each day against your goal. Under a weight log it draws the trend. Delete the word and it’s gone.
29 pages, one keyword each
Every example below is calculated live by Plainsum, right now, in your browser.
Start with a blank page
Free. No account, no card. Your pages stay on your device.
Open PlainsumQuestions
Where are my pages saved?
In your browser on this device. Nothing is sent anywhere, which is also why results show up instantly.
Do I need to learn any code?
No. You type the way you’d write a note. Type /help on any line to see every page type, command, and abbreviation.
Where do the calories come from?
From USDA FoodData Central (SR Legacy, 2018), which includes some fast-food items. For anything missing, type the calories once, like shake shack burger 530 cal, and Plainsum remembers it.
Are currency conversions live?
No. Plainsum uses fixed, approximate rates and marks those answers with ≈. Set your own with a line like 1 eur = 1.10 usd.
Is there a desktop app?
Not yet. Plainsum runs in your browser for now.