Free & Ad-Free Calculators

The numbers
that actually
matter.

25+ precision calculators for finance, property, health & research. No ads. No tracking. Just answers.

Start Calculating Academic Tools
compound-interest.calc
Principal
$10,000
Rate / yr
7.00%
Period
20 years
Monthly
+$200
Future Value
$91,468
+$41,468 interest earned
Compound InterestMortgage CalculatorH-Index CalculatorBMI CalculatorP(doom) CalculatorCarbon FootprintHome AffordabilityLongevity ScoreRental Property ROIAcademic Career ProjectionWedding BudgetPet Cost EstimatorCompound InterestMortgage CalculatorH-Index CalculatorBMI CalculatorP(doom) CalculatorCarbon FootprintHome AffordabilityLongevity ScoreRental Property ROIAcademic Career ProjectionWedding BudgetPet Cost Estimator
25+
Calculators
0
Ads or Paywalls
100%
Client-Side
∞
Always Free
// Calculator Categories
Financial calculators
Financial
Financial Calculators

Compound interest, savings, investment returns, salary comparison.

6 calculators →
 Property calculators
Property
Property Calculators

Mortgage payments, home affordability, rental property ROI.

4 calculators →
 Health calculators
Health & Personal
Health Calculators

BMI, carbon footprint, longevity, pet costs, wedding budget.

8 calculators →
 Academic calculators
Academic
Academic Calculators

H-Index, G-Index, career projection, P(doom) — for researchers.

4 calculators →
// Most Used
CI%
Compound Interest

See exactly how your money grows. Principal, rate, frequency, contributions — full amortization.

Calculate →
MTG
Mortgage Calculator

Monthly payments, total interest, full amortization schedule for any loan.

Calculate →
H-i
H-Index Calculator

Measure your research impact instantly. Paste citation counts, get your H-Index and G-Index.

Calculate →
BMI
BMI Calculator

Body Mass Index with WHO categories. Metric and Imperial. Includes waist-to-height ratio.

Calculate →
Pd
P(doom) Calculator

Estimate your personal AI existential risk probability. Based on Eliezer Yudkowsky’s framework.

Calculate →
CO2
Carbon Footprint

Estimate your annual CO₂ emissions from transport, energy use, diet, and lifestyle.

Calculate →
PET
Pet Cost Calculator

Annual and lifetime costs of pet ownership — dog, cat, rabbit and more.

Calculate →
$$
Salary Comparison

How long does it take Elon Musk or Taylor Swift to earn your annual salary?

Calculate →
LIF
Longevity Suite

Healthspan projector, bio-aging reversal checker, and longevity progress tracker.

Calculate →
// Why Calcuja

Calculators without
the clutter.

Most calculator sites are filled with ads, dark patterns, and tools designed for engagement metrics rather than actual answers. We built Calcuja for the opposite — clean interfaces, honest results, zero monetization tricks.

NO
Zero ads, zero paywalls

No premium tiers. No tracker scripts. No cookie walls interrupting your work.

⚡
Instant, in-browser results

No page reloads. Your data never leaves your device. Results appear as you type.

OK
Built for real decisions

Each tool is designed around an actual question you're trying to answer — not to maximise session time.

25+
Free calculators
0
Ads or paywalls
4
Categories
DE
GDPR compliant
From the blog