When a wrong number is a correction.
News sites, personal finance publishers, and software platforms put our calculators in front of millions of readers. There’s no sales funnel here. The product is a number your audience can rely on, delivered fast and rendered cleanly.
Publishers have run our calculators for over 30 years.
| Accuracy | Verified against 30 years of production results |
|---|---|
| Coverage | 177 calculators across 15 families |
| Delivery | Embed on your pages, or call the API |
| Accessibility | Designed to conform to WCAG 2.2 Level AA |
Editorial standards, applied to math.
A calculator embedded in an article carries your masthead. Ours are built so that’s a safe thing to do.
Nobody hand-writes the math
Each calculation starts as an analyst’s workbook, is compiled into code, and is tested against decades of production results before release. How the engine works
Results that don’t drift
A compatibility gate blocks any change that would break an existing contract, so a calculator you embedded last year behaves the same today.
Nothing loaded from third parties
No trackers or outside scripts run inside the calculator, which keeps your privacy policy and consent banner simple.
Accessible to your whole audience
Keyboard and screen reader support, contrast, and reduced motion, designed to WCAG 2.2 Level AA. Our accessibility statement
Reads on every screen
Calculators fit narrow article columns and phone screens, with an optional script that sizes the frame to its content.
Your look, not ours
Colors, fonts, and wording follow your style guide, so a calculator reads as part of the piece it sits in.
Two ways to use it.
Most publishers start with embeds and move to the API when they want a custom experience.
| Compared | Embed | API |
|---|---|---|
| Best for | Articles, evergreen tools, and tool pages | Custom interfaces inside your product or CMS |
| You build | Nothing. Paste a code snippet | The interface; we return the numbers |
| Styling | Configured in the console | Entirely yours |
| Math | Same verified engine | |
Licensing for publishers is quoted on usage rather than per calculator. Tell us your page views and where the calculators will appear.
What your readers get.
The same tools people use on their bank’s or insurer’s site, without a sales pitch attached.
- Answers to the questions they came for
Mortgage payments, take-home pay, debt payoff, retirement income, and more than 200 others.
- Results they can keep
Visitors can download a PDF of their results or have them emailed.
- No data collection by default
Lead capture is off unless you turn it on, so a calculator is just a calculator.
- English and Spanish
Reviewed by people before publication, with more languages on request.
Getting started.
Developers can try every calculator today on the free API plan; licensing follows when you know what you need.
- Step 1
Try the API
Create a key on the free plan and call any calculator.
- Step 2
Pick a delivery
Embed calculators on your pages, call the API, or both.
- Step 3
Agree on terms
We quote on usage and where the calculators will appear.
- Step 4
Publish
Paste the embeds or ship your own interface.
Questions from publishers and platforms.
Do you require attribution on the page?
Standard placements include a small “Powered by FinCalc” credit. A white-label option removes it for an additional fee.
Will an embedded calculator hurt our page speed or SEO?
The calculator loads in its own frame, so it can’t block your page or interfere with your scripts, and it makes no third-party requests. Your article’s text, headings, and links stay yours for search engines to index.
Can we build our own interface?
Yes. The API returns typed results for every calculator, documented in an OpenAPI specification. See the developer overview
What happens if a calculation changes?
Calculations are versioned, and a compatibility gate blocks changes that would break an existing contract. When a formula changes because a tax rule or limit changed, we tell you.
Can we syndicate calculators to partner sites?
Tell us where they’ll appear and we’ll structure the license around it.
Talk to us about licensing.
Tell us where the calculators will run and roughly how much traffic they’ll see, and we’ll put together terms. Developers can start on the free API plan today.