Calculate a percentage of any number instantly.
71 tools · 8 categories · always free
Free Online Calculators for Everyday Decisions
Clear, reliable calculators for money, work, health, study and everyday decisions.
Instant results
Transparent formulas
Private by design
CalcOcean essentials
Calculators people rely on
Accurate answers, transparent formulas and no sign-up.
Estimate monthly payments, total payment and total interest.
Estimate a mortgage payment from price, down payment, rate and term.
Calculate your exact age from your date of birth.
Calculate BMI from height and weight, with adult screening categories and their limitations.
Project investment growth with monthly compounding.
Convert annual salary into monthly, weekly and hourly pay.
Find the final price and savings after a discount.
Average course grade points to estimate a GPA on a 4.0 scale.
Measure the return and net gain on an investment.
Find the exact number of calendar days between two dates.
Add VAT to a net amount and see the tax breakdown.
Organized for clarity
Explore by category
A clear home for every kind of calculation.
Clear tools for percentages, discounts and practical number problems.
16 Calculators
Estimate borrowing, taxes and long-term investment growth.
7 Calculators
Make informed decisions about salary, margins and investment returns.
12 Calculators
Calculate ages and exact durations between calendar dates.
4 Calculators
Calculate grades, GPA targets and classroom results with transparent steps.
3 Calculators
Informational estimates for body measurements and daily energy needs.
17 Calculators
Convert common metric, imperial, scientific and digital units with explicit standards.
9 Calculators
Useful tools for travel, household energy and daily choices.
3 Calculators
Our approach
Made for decisions, not distractions.
These free online calculators turn everyday questions into clear answers for better decisions. Every tool explains the formula, shows practical examples and works directly in your browser.
Fast Private Explained
FAQ
Good to know
Is CalcOcean free?
Yes. Every calculator is free to use, with no account required.
Are results reliable?
We use standard formulas and show the method. Financial and health results are estimates and should be checked for important decisions.
How are calculations performed?
Values are processed in your browser. Each calculator shows the formula, assumptions and a practical example so you can understand and check the result.
What happens to my inputs?
CalcOcean does not require an account. Where calculation history is available, up to 50 successful calculations are stored only in this browser profile and can be deleted from the History page.
Which languages are available?
All 71 calculators are available in English, French, Spanish, German and Arabic. Guides and blog articles may have a smaller set of translated versions.
How can I report a problem?
Email support@calcocean.com with the page URL, non-sensitive sample values, the expected result and the actual result. Never send private financial, tax or medical records.
From question to answer
- 1
Choose the tool that matches your question.
- 2
Enter your values using the units shown.
- 3
Calculate, then read the result and its explanation.
Understand the formula
These are the actual formulas used by the linked tools.
Percentage Calculator — formula
R = A × p ÷ 100
Loan Calculator — formula
M = P × r(1+r)ⁿ ÷ ((1+r)ⁿ − 1)
Salary Calculator — formula
M = A ÷ 12 · W = A ÷ 52 · H = A ÷ (52 × h)
See the numbers in practice
Use these worked examples as a reference before entering your own values.
Percentage Calculator — worked example
150 × 20 ÷ 100 = 30
Loan Calculator — worked example
P = €250,000 · r = 4.5% ÷ 12 · n = 20 × 12 = 240
Salary Calculator — worked example
€60,000 ÷ 12 = €5,000 · €60,000 ÷ 52 = €1,153.85