Expression Calculator
Work through a calculation line by line with named variables, functions such as sqrt, log, round, min and max, and constants pi and e, with every result shown.
Free · No sign-up · Your inputs stay in your browser
Input
A calculator that shows its working
Output
4.44288293816
| Line | Value |
|---|---|
| rps | 1,200 |
| latency | 0.085 |
| workers | 133 |
| memory_gb | 8.3125 |
| sqrt(2) * pi | 4.44288293816 |
Each line can use the variables defined above it, which makes a back-of-the-envelope estimate (capacity, cost, storage) readable and easy to adjust later. Arithmetic is in doubles, so 0.1 + 0.2 shows 0.3 only because results are rounded to 12 significant digits. ^ and ** are both powers; trigonometry is in radians.
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About this tool
Method, assumptions, practical next steps, and limits.
Back-of-the-envelope maths
Capacity estimates, cost projections and storage sums are easier to check when every step is named: requests per second, average latency, workers needed, memory per worker. Change one input and every line below updates, which a phone calculator cannot do.
Floating point
Arithmetic is in doubles, so results carry the usual binary rounding, hidden here by rounding the display. For money use integers of cents, and for large exact integers use the big number calculator. Trigonometric functions take radians.