Money With Clo · Free UK mortgage tools

Mortgage tools & calculators

Mortgages can get surprisingly confusing once you get beyond the monthly payment. Start with the question you’re trying to answer and I’ll point you to the tool I’ve built for it.

Free to useNo account neededBuilt around real mortgage questions
Start here

What are you trying to work out?

You don’t need to know the name of the calculator. Pick the question that sounds most like yours.

Where is my mortgage payment actually going?

Mortgage Payment Breakdown Calculator

See how your monthly payment splits between interest and paying down your mortgage balance, then explore how regular or one-off overpayments could change the interest you pay and how quickly the balance falls.

Example view
Interest39%
Paying down the mortgage61%
See where my payment goes
How much can I overpay without an Early Repayment Charge?

Mortgage Overpayment Allowance Calculator

Check how your lender works out its overpayment allowance, estimate how much you may have left and see whether a planned overpayment appears to fit within it.

Example result £12,000 left
40% of example allowance used
Check my overpayment allowance
Still not sure?

Which mortgage calculator should I use?

Here are the kinds of questions each one is designed to answer.

Money With Clo mortgage planning illustration
Why I built these

I was already answering these questions anyway

I’ve somehow become the person friends and family tend to come to with money questions, particularly anything involving mortgages, overpayments and working out what the numbers actually mean.

I’ve spent a lot of time helping people work through these things over the years, alongside figuring them out for my own mortgage. Eventually I started turning some of the explanations I was already giving into simple tools for them and for me, then thought they might be useful to other people asking the same questions too.

I’m building Money With Clo in my spare time, so this mortgage toolkit will grow over time. If there’s a mortgage question you wish was easier to answer, I’d genuinely like to hear it.

Help shape what comes next

What mortgage question should I tackle next?

These tools started with questions people were already asking me. Pick the problem you’d most like a tool for, or tell me what I’ve missed.

Choose a mortgage question

About these mortgage tools

Free and no account

You can use the calculators without creating an account or handing over your mortgage details.

Different tools for different questions

The payment calculator explains the maths of your mortgage. The allowance calculator focuses on lender-specific overpayment limits and ERCs.

Built to grow

I use feedback from real questions to decide what to research and build next rather than adding calculators for the sake of it.

These tools explain mortgage calculations and lender rules. They don’t assess whether a particular mortgage decision is right for your circumstances.