keepcalculator

Free calculators, filed by subject

Every calculator on its own card

Find the card, change the numbers, and keep the answer with the formula and a worked example beside it.

Cards on file
84
Drawers
10
Formula shown
every card

The ten drawers

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How every card is kept

Read the method →
  1. 01Textbook formulaEach card uses the standard equation and prints it, with every variable, unit and constant.
  2. 02Realistic defaultsThe card opens with a worked case. Change any number and the answer updates as you type.
  3. 03Stated roundingEach result says how many decimals it keeps, so you know what to copy.
  4. 04Checked exampleThe worked example repeats the sum step by step with the default numbers.