Calculator
An EE calculator that speaks 4k7 and 2M2
Type values the way they are printed on a resistor: 4.7k, 100n, 2M2. The Calc tab is free and works offline.
iOS and Android, beta this winter.
Keypad and expression line
The expression line has a keypad with digits, + − × ÷ ^ ( ), ±, a decimal point and SI prefix keys p n µ m k M G. The ∥ key is the parallel operator. There are common functions (√, x², 1/x, log, ln), ANS, backspace and clear.
Engineering input
The calculator accepts 4.7k, 100n, 2M2 (= 2.2 M) and 4k7. The prefix can sit after the number or in place of the decimal point. ×, ÷ and − work as multiply, divide and minus.
Results
Results show with an automatic SI prefix and 4 significant digits by default. A setting changes this to anything from 3 to 8. Long-press a result to see the exact value and copy it. A parse error shows its position, for example "Unexpected ')' at 14".
History
The history keeps your last 50 calculations on the device. Tap one to reuse it.
Divide by zero
Dividing by zero shows "—" with the reason. There is no error dialog, and the result is never an infinity sign. A parallel with a zero operand counts as division by zero.
What it does and doesn't do (yet)
| What it does | Plan |
|---|---|
| A calculator with SI prefix keys, engineering input such as 4k7 and a parallel operator. | Free |
| A safe expression evaluator behind the calculator, with no scripting engine. | Free |
Not yet, or not planned
- Formulas reference the current run only; no cross-run analytics.
Questions
Can I type 4k7 or 2M2?
Yes. 4k7 is 4.7 k and 2M2 is 2.2 M.
What happens on divide by zero?
The result shows "—" with the reason. It never shows an error dialog or an infinity sign.
Is there a history?
Yes. The history tape keeps the last 50 calculations, and a tap reuses one.
Coming to iPhone and Android.
iOS and Android, beta this winter.
Questions or a meter to suggest? Mail support@testnmeasure.app.
No ad networks, no sign-up.