A free Calculator.net alternative that runs in your browser
Calculator.net is the most popular calculator site, with 61 million visits a month across 216+ pages. It's free, no signup, and the math is correct. The trade-off: every page is wrapped in Google AdSense slots, the design is dated, and the site tracks every visit. Uttir covers the same common calculators plus 10+ specialty ones (discount, body fat, ideal weight, pregnancy, retirement, inflation, work hours, pace, square footage, macro), with no ads, no tracking, and a UI built for phones.
Quick answer
If you want a free calculator collection that respects your privacy and works as well on a phone as on a laptop, use Uttir. It has the standard calculators Calculator.net has (BMI, mortgage, percentage, age, tip, calorie, compound interest) plus 10+ specialty ones (discount, body fat, ideal weight, pregnancy, retirement, inflation, work hours, pace, square footage, macro). No ads, no signup, no daily limit, no upload. The trade-off: Uttir is a focused collection, not a 216-page encyclopedia. Calculator.net still wins on coverage of obscure domains (chemistry, civil engineering, etc.) that Uttir doesn't cover.
Feature comparison
| Feature | Uttir | Calculator.net |
|---|---|---|
| Free, no signup, no account | ||
| Standard calculators (BMI, mortgage, percentage, age, tip) | ||
| Specialty calculators (discount, body fat, ideal weight, pregnancy, retirement, inflation, work hours, pace, square footage, macro) | ||
| Multiple calculation modes in one tool (e.g. discount forward/reverse/markup) | ||
| Mobile-friendly with no click-to-reveal buttons | ||
| Dark mode follows system preference | ||
| No ads, no ad scripts, no ad tracking | ||
| No upload (everything runs in the browser) | ||
| No daily limits | ||
| No Google Analytics, GTM, or third-party scripts |
Try the discount calculator
One of the most-searched calculator queries. Use it right here.
The full calculator list
Every entry links to a working tool that runs in your browser.
- Discount calculator /discount-calculator
X% off, what % off, or required discount to hit a target
- Body fat calculator /body-fat-calculator
U.S. Navy method from neck, waist, and (for women) hip
- Ideal weight calculator /ideal-weight-calculator
Devine, Robinson, Miller, Hamwi plus a healthy BMI range
- Work hours calculator /work-hours-calculator
Add up a week of clock-in/out with daily and weekly overtime
- Pregnancy calculator /pregnancy-calculator
Due date from LMP or conception date; week, trimester, milestones
- Pace calculator /pace-calculator
Run/cycle pace from time+distance, or finish time from pace
- Square footage calculator /square-footage-calculator
Single room or whole floor in square feet and meters
- Inflation calculator /inflation-calculator
Future cost and purchasing power at a custom or historical CPI rate
- Retirement calculator /retirement-calculator
Project savings with contributions, raises, and inflation
- Macro calculator /macro-calculator
Daily protein, carb, and fat grams from a calorie target
- BMI calculator /bmi-calculator
Body mass index with metric or imperial units
- Calorie calculator /calorie-calculator
BMR + TDEE with a goal-adjusted daily calorie target
- Mortgage calculator /mortgage-calculator
Monthly payment, total interest, amortization
- Compound interest calculator /compound-interest-calculator
Future value with monthly contributions
- Tip calculator /tip-calculator
Tip + split-the-bill math with quick presets
- Percentage calculator /percentage-calculator
Any percent-of, percent-change, or percent-difference problem
- Age calculator /age-calculator
Exact age in years, months, days
- Date calculator /date-calculator
Days between two dates
What stays the same
Both sites are free, no signup, and run the math in the browser. The output values for the standard calculators (BMI, mortgage, percentage, age, tip) match to several decimal places because the underlying math is the same.
What Uttir does differently
- No ads. Calculator.net loads ~500 KB of Google AdSense scripts on every page before you see the calculator. Uttir has no ads. The whole page is the tool.
- No tracking. No Google Analytics, no Google Tag Manager, no third-party scripts on tool pages. Your calculation history is not recorded anywhere.
- No click-to-reveal. Every result updates as you type. Calculator.net has the answer, but the page makes you click "Calculate" to see it (to force a second ad impression).
- Mobile-native. The calculators are built for phones — big tap targets, numeric keyboards, instant feedback. Calculator.net's design is desktop-first and the buttons are tiny on mobile.
- Dark mode. Uttir follows your system preference. Calculator.net is always white-on-light-blue.
- Multi-mode tools. The discount calculator does forward, reverse, and required-discount in one tool. Most calculators on Calculator.net are single-purpose.
What Uttir does not do
- 216+ calculators across obscure domains. Calculator.net has pages for chemical molarity, structural engineering, civil construction, and dozens of other specialty domains. Uttir targets the 20 most useful calculators, not the long tail.
- Highly specialized engineering calculators. Concrete volume, rebar weight, asphalt tonnage, beam deflection — Calculator.net has all of these. Uttir has the everyday math, not the engineering reference book.
Verify the no-tracking claim
Open any Uttir tool. Open DevTools, go to the Network tab, and run a calculation. The only requests are the static assets that make up the page. There is no analytics call, no third-party fetch, no upload. The math runs in JavaScript on your device.