SoloRateCalc is a collection of free arithmetic calculators for freelancers, contractors and one-person businesses. Every tool on the site does one thing: apply a mathematical formula to the numbers you enter and return a result.
Why it exists
Many of the financial decisions a freelancer faces every week — what to charge, what to set aside for tax, whether a project is worth taking, whether the business broke even this month — involve arithmetic that is not difficult once you know the formula, but easy to get wrong in your head or in an ad-hoc spreadsheet. The goal of this site is to make those formulas accessible, explicit and verifiable, not locked away in a black box.
There is no account to create, no subscription and no paywall. Every calculator runs directly in your browser. The numbers you type in are processed locally by JavaScript and are never transmitted to any server. There is no data collected, no profile built, and nothing stored beyond your own consent preference if you choose to accept optional cookies.
The site is not funded by selling results, recommendations or referrals. When it has enough traffic to warrant it, contextual advertising through Google AdSense will be added — and that will be disclosed before it is switched on. Until then, the tools are simply here to be used.
How the calculators work — pure arithmetic
Every calculator on this site is pure arithmetic. It takes the numbers you enter, applies a mathematical formula, and returns a result. No rates, figures or data are retrieved from any government body, official publication, financial institution or external database. The calculator knows only what you type into it.
This is a deliberate design decision. Tax rates change. Payment-processor fee schedules change. A calculator with today's official rate baked in will silently produce wrong answers once those rates change — and the user has no way to know the number is stale. The approach here is the opposite: you supply every rate that matters, and the calculator does only the multiplication and division. The tool cannot become outdated because it contains no data to go out of date.
Where a calculator shows a default value — a suggested tax rate, a typical markup percentage, a common fee structure — that default illustrates the formula with a concrete example. It is a starting point for exploration, not an authoritative figure for a specific jurisdiction. Replace any default with the value that applies to your actual situation before you act on the result.
Every result shows the formula and a full step-by-step breakdown. This is intentional: the goal is not just to return a number but to show the arithmetic, so you can verify it, understand the method, and carry it forward even without this site.
What the calculators cover
The tools are grouped into four areas that represent the main financial decisions a one-person business handles regularly.
Pricing and rates — Five tools for working out what to charge. The hourly rate calculator builds a rate from the ground up: your income target, your costs, your realistic billable hours and a tax set-aside. The day rate and project quote calculators translate that hourly floor into per-day and per-project prices. The markup and profit margin calculators show whether a given price contains the profit percentage you were aiming for.
Taxes — Three tools for estimating tax obligations. The self-employment tax calculator multiplies your net profit by the rate you enter. The quarterly tax calculator adds an income tax layer and divides the total by four. The take-home calculator combines both layers to show what remains after both are subtracted. In all three, you enter the rates; the calculator applies them.
Invoicing and payments — Three tools for the mechanics of getting paid. The invoice calculator builds a total correctly: discount applied before tax, not after. The payment-processor fee calculator shows what a platform takes per transaction and what reaches your account. The late-payment fee calculator works out interest on an overdue invoice at the contractual rate you specify.
Business health — Three tools for stepping back from individual jobs. The break-even calculator finds the monthly sales volume that covers your fixed costs exactly. The net profit calculator builds a simplified income statement from revenue, costs and taxes. The billable hours calculator measures what fraction of your working time actually generates income, and what your annual revenue ceiling is at your current rate and utilisation.
What the calculators deliberately exclude
The tool selection is governed by one rule: a calculator must produce a useful result from arithmetic alone, without requiring professional expertise to interpret. If a tool would need a licensed professional to make the output meaningful — a medical risk estimator, a legal fee calculator, a regulated investment return — it does not belong here.
The calculators also exclude any field that requires importing or maintaining external data. There are no mortgage tools that look up current rates, no currency converters that fetch exchange rates, and no tax calculators that apply official brackets. These are all possible to build, but they create a maintenance problem and an accuracy risk. A tool that only processes what you put in cannot produce wrong answers because of something that changed outside of it.
Results are estimates
Every result on this site is a planning estimate. It is arithmetic applied to your inputs under the formula shown on the page. It accounts for nothing outside those inputs — no deductions, no credits, no income thresholds, no jurisdiction-specific rules, no legal structure, no individual circumstances beyond what you have entered.
For a rough figure to help you understand the shape of a financial decision, these tools are appropriate. For a figure you intend to act on — a price you will quote, a tax amount you will file, a profit you will report — verify it with a qualified and licensed professional who knows your full situation. Using this site does not create any advisory or professional relationship.
Get in touch
Suggestions for a calculator that would fit this scope, corrections to an existing formula, or anything else: contact@soloratecalc.com.