Calculators
Everyday arithmetic that is annoying to do by hand: dates and ages, percentages, loans and EMIs, tax, health metrics and more. Each one shows the working, not just the answer, so you can check it rather than trust it.
25 tools · 25 run entirely in your browser
Age Calculator
Years, months, weeks, days, hours and seconds since DOB.
In-browserAverage Calculator
Mean, median, mode and range from a list of numbers.
In-browserBMI Calculator
BMI with imperial and metric units, plus risk bands.
In-browserChronological Age Calculator
Exact age in years, months, days for clinical assessments.
In-browserConfidence Interval Calculator
95 % / 99 % CI for proportions and means.
In-browserCPM Calculator
Cost-per-mille for ad spend at any impression volume.
In-browserDiscount Calculator
Sale price, savings and effective discount in one step.
In-browserEarnings Per Share Calculator
Compute basic + diluted EPS from net income & shares.
In-browserGPA Calculator
Weighted, unweighted and cumulative GPA in one form.
In-browserGrade Calculator
Weighted grade across assignments and exams.
In-browserGST Calculator
Add or remove GST at any rate with a clean breakdown.
In-browserHours Calculator
Add/subtract hours, minutes and seconds across a workday.
In-browserInvestment Calculator
Future value with regular deposits and compounding.
In-browserLoan Calculator
EMI, total interest and amortisation schedule for any loan.
In-browserLoan-to-Value Calculator
LTV ratio from loan amount and property value.
In-browserMargin Calculator
Gross margin, mark-up and revenue from cost + price.
In-browserPayPal Fee Calculator
Estimate PayPal fees by region and transaction type.
In-browserPercent Change Calculator
Signed percent change between any two values.
In-browserPercentage Calculator
Solve every common percentage problem — of, change, off.
In-browserPercentage Decrease Calculator
Percent change from a higher number to a lower one.
In-browserPercentage Difference Calculator
Symmetric percent difference between two values.
In-browserPercentage Increase Calculator
Percent change from a lower number to a higher one.
In-browserProbability Calculator
Joint, conditional and complementary probability.
In-browserSalary Calculator
Hourly ↔ annual ↔ monthly ↔ weekly with tax estimates.
In-browserSales Tax Calculator
Add or remove sales tax/VAT/GST at any rate.
In-browserFrequently asked questions
How many Calculators does ToolMunch have?
25 right now, and every one of them runs entirely in your browser. The grid on this page is the complete set — it is generated from the catalogue, so it is never a stale list.
Are the Calculators free to use?
Yes, all 25 of them. No trial, no premium tier holding back the main feature, and no daily or hourly cap on how many times you can use one.
Do I need an account to use the Calculators?
No. There is no account, no email address, and no login. Open the tool you need, do the job, and take the result.
Where do the Calculators do their work?
On your own device. Every tool on this page does its work inside your browser tab, so nothing you open or type is uploaded and there is no copy of it sitting on a server.
Do the Calculators work on Mac, Windows, and phones?
Yes. Everything here runs in a modern web browser on Windows, macOS, Linux, Chromebook, Android, and iOS. There is nothing to download or install.