Free online tools · verified math
Calculators that show their work.
Every result on TrueSums comes with the formula it used, the sources behind it, and the date the data was checked. No black boxes.
Example · freelance day rate
- Income target / yr
- $72,000
- Billable weeks
- 46
- Days per week
- 4
= 72,000 ÷ (46 × 4)
Formula shown with your numbers — on every tool
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Built for the math a specific job actually runs into.
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The TrueSums standard
Formula cited
Every calculation names its method and links the source it came from.
Tested against known answers
Each tool must reproduce five published test cases before it ships.
Dated data
Anything that changes — rates, limits, guidelines — shows when we last checked it.