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Loan Comparison Calculator

Put two loan offers side-by-side on the same amount or compare two different amount/term combinations.

Short answer

The cheapest 'monthly' isn't always the cheapest 'overall'. A longer term lowers the monthly cost but adds interest. APR is the fairest single number to compare offers on.
Step 1 of 20%

Loan A

£
%

How it works

Both loans are computed with the standard annuity formula. We multiply the monthly payment by the number of months to get total cost, then subtract the principal to show interest.

Worked example

£10,000 over 3 years at 9.9% vs £10,000 over 5 years at 7.5%:

  • 3y/9.9%: £322/m, total £11,604, interest £1,604
  • 5y/7.5%: £200/m, total £12,022, interest £2,022
  • Lower APR but longer term costs £418 more

Who should use this

  • Comparing two formal loan quotes
  • Deciding term length on a single offer
  • Refinancing existing debt

Common mistakes

  • ×Comparing on monthly only — missing the term effect
  • ×Using flat rate vs APR (not equivalent)
  • ×Forgetting that 'representative APR' is offered to only ~51% of accepted applicants

Frequently asked questions

Should I always pick the lowest APR?

Usually yes for the same term. But a longer-term loan with the same APR costs more total.

Is a longer term ever better?

Only if you genuinely need the lower monthly. You'll always pay more interest.

What's the cheapest UK loan rate currently?

For prime borrowers in 2025-26, around 6-8% APR on £7,500-£25,000 over 3-5 years.

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