Privacy Policy
Last updated 9 September 2026
• Our promise
Sum Calculator is built around a single rule: your numbers never leave your device. We do not send your calculation inputs or results to our analytics services. We use Google Analytics, Umami, and self-hosted Plausible at s.xi-ang.cc to measure website visits and pages. Plausible does not use cookies. Google Analytics and advertising services may use cookies and process request information.
• What actually happens
| Step | Action | Where the data sits |
|---|---|---|
| You open Sum Calculator | Static page downloads via HTTPS | Your browser cache |
| You type or paste numbers | Input stays in JavaScript memory | Your browser RAM |
| You press Calculate | Addition runs with native JS math | Your browser CPU |
| You close or reload | Memory is cleared automatically | Nothing persists |
• Data we do not collect
- •Numbers you enter or paste
- •The resulting sum, count, or average
- •Uploaded file contents sent to analytics services
- •Calculation inputs sent to analytics services
- •Calculation results sent to analytics services
• Embedded Sum Calculator
If you embed Sum Calculator in an iframe on your own site, the same rules apply:
- •All maths still run in each visitor's browser
- •Calculation inputs are not sent to our analytics services or to the host page
- •Each iframe session is isolated and wiped on close
• Security measures
- •HTTPS only – every byte travels inside TLS 1.3
- •No third-party scripts – we load zero trackers, ads, or social widgets
- •Open source – code is on GitHub so anyone can verify these claims
• Server-side logs
Our hosting provider keeps basic access logs (time-stamp, status code) for abuse prevention. Logs never contain calculation data and roll off automatically after 7 days.
• Contact
Questions about this policy? Email privacy [at] sumcalculator.org — we answer within 48 hours.
• Plain-language summary
Use Sum Calculator with confidence: the numbers you enter stay on your screen, run in your browser, and disappear when you leave. We will never ask for them, look at them, or sell them.