Hi, I'm Alex Chen — the developer behind Calcs.top. I built this site because I was tired of online calculators that were either buried in ads, confusing to use, or just plain wrong. Every tool on this site is built using standard, publicly documented formulas that I've verified against authoritative references.
My Story
As a software developer, I've always been frustrated by how many online tools sacrifice accuracy for ad revenue. I wanted to create a calculator site that was genuinely useful: accurate formulas, no forced sign-ups, and results you can actually trust. I handle the development, formula verification, and content for this site personally.
Mortgage, loan, tax, ROI, and investment calculators. Formulas sourced from IRS publications, Federal Reserve guidelines, and standard financial textbooks.
BMI, BMR, calorie, heart rate, and sleep calculators. Formulas referenced from WHO, CDC, and NIH guidelines.
Scientific calculator, percentage, quadratic solver, physics, and chemistry tools. Formulas verified against NIST reference data and standard textbooks.
Developer tools, unit converters, and construction calculators. Formulas cross-checked with IEEE standards, RFC specifications, and building codes.
My Verification Process
Every calculator on Calcs.top goes through a structured verification process before publication. Here's how I make sure the tools return correct results.
I identify the authoritative source for each formula: WHO guidelines, IRS publications, NIST reference data, ASHRAE standards, or peer-reviewed textbooks. No formula is accepted from secondary or unverifiable sources.
Each formula is implemented independently and compared against known reference values. If results diverge by more than rounding error, the discrepancy is resolved before proceeding.
Every calculator is tested with zero inputs, extreme values, and known reference cases. Results are compared against established benchmarks.
The formula source and any relevant limitations are documented on the calculator page itself, so users can verify the math independently.
My Values
All calculations run locally in your browser. I do not collect, store, or transmit your inputs. I never have and never will.
Where space allows, I cite the authoritative source for every formula directly on the calculator page. You can verify the math yourself.
Tax rates change, IRS mileage limits update, CDC guidelines evolve. I track regulation changes and update calculators accordingly, shown as "Last Updated" dates.
All calculators are free to use, with no registration required. I rely on advertising to keep the site running.
Found an error? Have a suggestion? I take correction reports seriously and respond within 48 hours.
Email: asunnyboy861@gmail.com
I do not respond to SEO pitches, link exchange requests, or sponsored content inquiries.