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Embed · Finance & Money · 94 calculators

Finance calculators for your website

Mortgage, salary, tax, VAT, rental yield, amortization — any of the 94 finance tools from the 1279-tool catalogue, live on your site with one iframe. Your visitors use them in their browser; you get a working calculator page without writing or maintaining the maths.

Why site owners embed these

One iframe. That's the install.No JavaScript libraries, no build step, no widget account. Paste it into WordPress, Webflow, Notion — anywhere that takes HTML.
Clean by designNo ad scripts and no paywalls in the embeds — your page keeps its speed and your visitors keep their privacy while using the tool.
Maintained, not abandonedUK statutory figures (2026/27 tax year) are tracked and enforced by 100 independent automated checks that run on every deploy. Your calculator stays correct in April.
Free tier is a real tierEmbedding costs nothing, forever. The small credit line is the whole price — a licence simply removes it and adds your brand.

The calculators people ask for by name

🏠 Mortgage Calculator
Calculate detailed mortgage payments with amortization schedules, extra payments analysis, and regional comparisons. 💰 Monthly payments • Total int…
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🏦 Mortgage Affordability — How Much Can You Borrow?
Lenders look at two things at once: an income multiple and an affordability stress test at a rate higher than you will actually pay. This works out…
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🏦 Mortgage Overpayment Calculator
See how overpaying cuts your mortgage term and total interest. Add a monthly overpayment, a lump sum, or both, and compare against paying the norma…
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🏦 LTV Mortgage Calculator
Loan-to-value = mortgage ÷ property price. UK product tiers often sit at 60, 75, 85, 90, 95%. Deposit is price − loan. Not a lender decision and no…
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📈 Loan & Mortgage Amortization Schedule Calculator
Calculate monthly loan payments, view complete annual and monthly amortization schedules, and simulate the interest savings of extra principal paym…
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💰 Salary Calculator
Calculate net salary after taxes, deductions, and contributions. ⚠️ Estimates only — consult a tax professional.
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💰 Tax Estimator & Calculator
Estimate income tax, national insurance, student loan repayments, and take-home pay for UK taxpayers — by week, fortnight, month, quarter or year.…
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💷 VAT / GST / Sales Tax Calculator
Add tax to a net price or extract tax from a gross (inc-VAT) figure. Presets cover UK VAT, common EU GST/VAT rates and US-style sales tax. Arithmet…
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🏠 Rental Yield Deal Analyser
Compare gross yield, net yield and monthly cash flow for a prospective rental property. All calculations stay in your browser.
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💰 Compound Interest Calculator
Calculate future value, growth projections, and compare investment scenarios. Visualize wealth accumulation over time with detailed breakdowns. ✅ F…
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💰 Retirement Calculator
Estimate your retirement savings growth with compound interest. ⚠️ Educational only — consult a financial advisor.
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🧾 Invoice Late Fee Calculator
Calculate statutory or agreed late-payment interest and a clear updated invoice total. All calculations stay in your browser.
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Plus 82 more in the category — budgeting, debt payoff, IR35, freelancer rates, stamp-duty-style deal checks and the rest of the money shelf. See all 94 →

Why the numbers can be trusted

The maths is easy to get wrong. The £100,000 personal-allowance taper creates a 60% marginal rate; modelling the basic-rate band as a fixed ceiling instead of a fixed width gets it wrong — and that exact bug has been found in commercial calculator products. Ours is tested against an independent implementation of the published HMRC rules, not against its own logic.

100 independent automated checks run on every deploy. If a change breaks a statutory computation, the build fails before it ships. The figures currently model the 2026/27 tax year: personal allowance £12,570 (frozen to April 2028), basic rate 20% to £50,270, higher rate 40% to £125,140, employee NI 8%/2%.

The update history is public. Statutory changes land with a dated entry in the changelog — the same evidence a buyer needs before trusting an unknown supplier with their clients' numbers.

Pricing — free forever, branded from £99

Embedding is free, forever, no account. The credit line under each tool is the entire price of the free tier. A licence removes it and puts your brand on the tool. Annual; cancel by not renewing; activation is a licence key you paste once.

Free embed

£0 / year
  • All 1149 tools, any site
  • Small credit line (required)
  • No ads, no accounts, no paywalls
Copy a snippet above

Single tool

£99 / year
  • One tool, one site
  • Credit line removed
  • Your logo on the tool
  • Statutory updates included
Enquire — £99/yr

Full white-label

£899 / year
  • All 1149 tools, unlimited sites
  • Your branding throughout
  • Self-host option
  • Statutory updates + priority fixes
Enquire — £899/yr

Prices are per year and include statutory updates while active. These calculators are estimating tools, not financial advice: figures are maintained against HMRC's published 2026/27 rules and enforced by 100 independent automated checks on every deploy — see the changelog. Visitors' inputs are processed in their own browser; the embeds collect nothing for us.

Questions, answered plainly

Is it really free to embed?

Yes. Every tool embeds free with a small credit line linking back here — that credit is the entire price of the free tier, and it works as a backlink for you too. No account, no sign-up, no API key.

How do I put a calculator on my site?

Pick a tool, click “Copy iframe”, and paste the snippet into any CMS, page builder or HTML page. It is a single iframe — no JavaScript libraries, no build step, no maintenance beyond keeping the snippet.

Can we remove the credit line and use our own branding?

That is exactly what the licence is for: £99/year for one tool, £299/year for a whole category, £899/year for everything white-label. You get a signed licence key; the credit disappears on your domain only.

Are these calculators financial advice?

No — they are estimating tools, not financial advice. The statutory figures (tax bands, National Insurance, student-loan thresholds) are maintained against HMRC's published 2026/27 rules and enforced by 100 independent automated checks on every deploy. See the changelog for the update history.

What do you collect from our visitors?

The calculators run in the visitor's browser and nothing they type is sent to us — there is no form submission anywhere in the embeds. This landing page itself measures traffic with Google Analytics; the tools record nothing.

Do you host the tools, or do we?

We host by default, so statutory updates reach every embed the day they ship. White-label licensees can additionally self-host the files.