Which calculator do you need? Start from the question
Nobody wants a calculator — they want an answer. Here is how to find the right tool by starting from the question you are actually trying to answer.
Start with the question, not the tool
Nobody wakes up wanting a calculator. They want an answer — what should I charge?, does this product make money?, can I afford this loan?. Find the question and the tool picks itself.
Here are the four questions that cover most of the maths a freelancer or small business does.
"What should I charge?"
The question every freelancer starts with. The freelancer rate calculator turns an income target into a floor hourly rate, and the project quote calculator turns scope into a project price.
Our guide to pricing your freelance services walks through both, including why the two numbers are different.
"Does this actually make money?"
Two tools answer it from different angles. The profit margin calculator shows the margin and markup on a single product or job. The break-even calculator tells you how many units you need to sell to cover your costs.
How to calculate profit margin explains the difference between the two, and why a healthy-looking markup can hide a thin margin.
"Can I afford this?"
For borrowing, the loan EMI calculator gives you the monthly payment, the total interest, and the total repayment — the three numbers that decide whether a loan is a good deal.
If you are choosing between borrowing and investing, the SIP calculator shows what the same monthly amount would build instead.
The shortcut
If you would rather not think it through, the tool finder quiz asks three questions and points you at one calculator. It is the same four questions above, just faster.
Browse everything
Every Plainso tool is free, needs no account, and works in any currency. And if none of them fits your question, tell us what you are trying to work out — the topic guides collect the tools and the explainers together.
Part of the Business guides.
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