Numbers you can check.

300+ calculators for pricing, tax, engineering and everyday decisions. Every formula is named and tested.

Browse all calculators How we build them
Free, no account300+ tools
Margin and markup
$
$
Gross margin34.6%
Markup on cost52.9%
Profit per unit$22.50
Updates as you type. Estimates only, see the disclaimer.
Formula sources named
If a standards body or tax authority defines it, the tool says which one.
Tested with worked examples
Hand-calculated cases are run against every tool before it publishes.
Estimates, not advice
Every result is for reference only. Nothing here is professional advice, so verify before you act.

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Largest first. Each tile shows its size, its archive, and three tools inside it.

Business & Trade81 Aspect Ratio CalculatorBill of Exchange CalculatorBill of Lading Late Fee Calculator Lifestyle51 Age in Days CalculatorAir Travel Packing Weight CalculatorAloe Vera Gel Dilution Calculator Agriculture22 Aquaponics Fish to Plant Ratio CalculatorCattle Grazing Rotation CalculatorCrop Breakeven Price Calculator Environment22 Annual CO2 Budget CalculatorBicycle vs Car Emissions CalculatorBiodiesel Blend Calculator Gaming22 Adventure Mode Completion EstimatorArmor Penetration CalculatorBattleground Rating Calculator Science & Engineering16 Acceleration CalculatorArc Flash CalculatorBattery Bank Calculator Education15 Academic Probability CalculatorAge Difference CalculatorClassroom Seating Arrangement Calculator Automotive13 Alignment Spec CalculatorBattery Charging Time CalculatorCar Lease vs Buy Calculator Home & Renovation12 Caulking Tube CalculatorCompost Volume CalculatorConcrete Slab Thickness Calculator Real Estate9 Debt Service Coverage Ratio (DSCR) CalculatorHome Selling Cost PlannerHouse Flipping Profit Calculator Technology9 API Rate Limit CalculatorAudio File Size CalculatorCluster Size Calculator Travel6 Bike Route Elevation CalculatorFlight Cost ComparatorFlight Time Calculator
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A printed worksheet of formulas, a desk calculator, a pencil and a steel ruler on a light grey desk
A printed worksheet of formulas, a desk calculator, a pencil and a steel ruler on a light grey desk.

How a calculator gets published here

The same four steps run every time, so you can judge how much to trust a result.

01

Start from a calculation people actually repeat

A tool earns its place when the same arithmetic keeps showing up in real work. One-off curiosities do not get built.

02

Find the definition that governs the answer

The source that defines the formula wins, and the tool names it. No single authority means the dominant convention, stated on the page.

03

Build it around your numbers

Labelled fields, the unit next to the value, results as you type, and nothing between you and the answer.

04

Test the edges before it goes live

Zero, negatives, blanks and very large values are all run through. A tool that silently returns a wrong number is worse than no tool.

An open notebook with hand-drawn bar and line charts beside a laptop and a cup of coffee

Who writes here

Ray Calder, editor Pulse Beam

Ray writes and maintains the calculator library. The work is checking that the formula behind each tool matches the source that defines it, that the units cannot be misread, and that the output is labelled an estimate rather than a verdict. He is not a licensed accountant, financial adviser, attorney or physician.

Role
Editor and maintainer
Library
300+ calculators
Corrections
Reviewed within 5 working days
Contact
[email protected]

Questions we get asked

Are the calculators free to use?
Yes. Every calculator on Pulse Beam is free, needs no account, and shows the result as you type.
Where do the formulas come from?
Where a standards body, tax authority or regulator defines the formula, that definition is what the tool uses, and the tool names it. Where no single authority exists, we use the convention most widely used in practice and print the assumption next to the result.
Can I rely on a result for a tax return, a contract or a medical decision?
No. Every tool returns an estimate from the numbers you type in, and it cannot check whether those numbers are right for your situation. Use it to get oriented, then confirm with a licensed professional.
A result looks wrong. What should I do?
Send the tool name, the values you entered and the result you expected through the contact page. Calculation errors go to the front of the queue and are normally reviewed within five working days.
Can I use the library in Bahasa Indonesia?
Yes. The calculators have Indonesian versions, and the whole Indonesian site lives under the /id/ path.

Start with the calculator you need

300+ tools, no signup, and a stated method behind each one.