Every number, worked out.
Mortgages, macros, matrices and more — precise answers in seconds, with the formulas shown.
Popular Calculators
Categories
BMI Calculator
Find your Body Mass Index and healthy weight range.
Calorie & Macro Calculator
Daily calories and protein, carb & fat targets.
Pregnancy Due Date Calculator
Estimate your due date and pregnancy timeline.
Body Fat Calculator
Estimate body fat percentage (U.S. Navy method).
Water Intake Calculator
A daily hydration target personalized to you.
Sleep Calculator
Bedtimes and wake times by sleep cycles.
Loan & Mortgage Calculator
Monthly payments, interest and full amortization.
Compound Interest & Savings Goal
See your savings grow with compound interest.
Tip & Bill Split
Tip amounts and per-person totals in seconds.
Scientific Calculator
Trig, logs, powers and full expression math.
Percentage Calculator
Percent of, what-percent and percent-change questions.
Age Calculator
Exact age in years, months and days.
Date Difference
Days, weeks and months between two dates.
Unit Converter
Length, weight, volume and temperature conversions.
AI Token Counter
Estimate token count for any text prompt.
GPA Calculator
Weighted GPA from course grades and credit hours.
Final Grade Calculator
What score you need on the final exam to reach your target grade.
Profit Margin Calculator
Profit, margin and markup from revenue and cost.
Markup Calculator
Selling price from cost and markup percent.
Mean, Median & Mode Calculator
Average, middle value and most frequent value of a dataset.
Standard Deviation Calculator
Sample and population standard deviation, variance and mean.
Fuel Cost Calculator
Trip fuel cost, gallons needed and cost per person.
Electricity Cost Calculator
Appliance energy use and what it costs to run.
Recently Added
Calculator Guides
All guidesHow to Calculate Hours Worked
Convert times to 24-hour format, subtract, handle breaks and overnight shifts — with the decimal table payroll uses.
Read guide StatisticsHow to Calculate Standard Deviation
The standard deviation formula worked through step by step — sample vs population, variance, and how to read the result.
Read guide StatisticsHow to Calculate Average
How to calculate the mean, when to prefer the median, and what the mode tells you — with worked examples.
Read guideWhy Calclu?
Instant results
Every calculation updates live as you type — no page reloads, no waiting.
Free to use
Every calculator is free, with no sign-up needed for everyday use.
Works anywhere
One clean, fast experience on your phone, tablet and desktop.
Your data stays yours
History, favorites and saved calculations stay private to your account.
Simple Pricing
Compare plansFree Account
Everything in guest, plus your personal hub. Every new account automatically starts on the Free plan.
$0.00/month
Most popularPlus
More power for heavy everyday use: higher limits, exports, and an ad-free experience.
$4.99/month
Pro
Unlimited calculations and advanced tooling for power users.
$9.99/month
Frequently Asked Questions
Is Calclu really free?
Yes. Every calculator works free, right in your browser, with no sign-up required. Optional paid plans add extras like unlimited history, exports and advanced analytics.
Do I need an account?
No — just open a calculator and start. Creating a free account syncs your history, favorites and saved calculations across your devices.
Which calculators are available?
Health, finance, math, time & date, education and everyday-life calculators — from BMI and loan payments to percentages, age and unit conversions. New ones are added regularly.
How accurate are the results?
Each calculator uses the standard published formula for its field and shows the formula on the page. Results are for information only — not medical, legal or financial advice.
