Work out UK Income Tax on rental profit for 2024/25, applying the finance cost restriction that gives mortgage interest a 20% tax credit instead of letting it be deducted as an expense.
Landlord Tax Calculator is a small tool that does one job while you watch. Nothing is saved, so a reload gives you a clean start.
Everything after the first page load is local. Pull the network cable mid-edit and the tool carries on as though nothing happened.
You will find it under Property, alongside 12 other tools for the same sort of job.
Runs in this tab, so nothing you type is uploaded.
annualRentalIncome: 15000 allowableExpenses: 3000 mortgageInterest: 6000 otherAnnualIncome: 30000
Property profit: 12000 Personal allowance used: 12570 Marginal tax band percent: 20 Tax on property profit before credit: 2400 Finance cost tax credit: 1200 Tax on property profit after credit: 1200 Effective tax rate on profit percent: 10
Yes. It is JavaScript running in this tab, so once the page has loaded it needs nothing further from the network. Put the machine in flight mode and it carries on. Nothing you do here is sent anywhere, because there is nowhere for it to go.
No. Reload the page and it starts from nothing. There is no account, no saved state and no cookie holding your last session. That is a deliberate trade: it cannot lose your data because it never keeps any.
Timing comes from performance.now(), the high resolution clock the browser provides, rather than from setInterval, which drifts by a few milliseconds every tick and compounds over minutes. What can still shift things is the browser throttling a tab in the background, so leave it visible if the timing matters.
Where a sound makes sense, it is generated with the Web Audio API rather than loaded as a file, so there is nothing to download and nothing to block. Browsers refuse to start audio until you have interacted with the page, which is why the first press is what switches it on.
Yes. The controls are sized for touch and the layout collapses to one column on a narrow screen. Bear in mind that a phone locking its screen will suspend the page, and timing stops with it.