How it works

Three steps, about a minute

You give it a payslip. It reads every line, checks each one against the rules that should have produced it, and tells you the difference in pounds.

1

Put a payslip in

Photograph it on your phone, paste a screenshot on a computer, or add the PDF from ESR. A whole folder at once if you have them saved up. Your contract of employment goes in the same place.

2

It reads every line

Basic pay, additional hours, banding, on-call, enhancements, tax, National Insurance, pension, student loan. Anything it was unsure of is flagged rather than guessed at.

3

You get a number

What you were paid, what you should have been paid, and the difference — with a letter to payroll or HMRC citing the exact figure and the rule it breaches.

Reading a photograph

Why a photo is enough

A payslip photographed on a desk is a hard thing to read: uneven light, a page that is never quite square, print at seven points. Several steps run before anything is recognised.

The page is found and flattened, so a photograph taken at an angle is mapped back to a rectangle. Uneven lighting is evened out — a shadow across the page otherwise thresholds a whole column of deductions into a solid block. Skew is corrected, because two degrees is invisible to you but moves the right-hand column a full row against the left. A payslip lying the other way round on the table is turned.

And then it checks itself

Every payslip is reconciled against its own printed totals: the pay lines must add up to total payments, the deductions to total deductions, and the difference to net pay.

If they do not, the slip is flagged and you are told which figure to look at. It would rather query a payslip than quietly report a wrong number, because you may end up sending a letter based on it.

What it checks against

The rules behind the numbers

Your contract

Pay point against the published scale, programmed activities, on-call supplement, banding, London weighting, and whether the payslip is built on the salary the contract states.

The pay circular

Basic pay against the current Pay and Conditions Circular for your grade and nation, full-time or less than full-time.

HMRC

The tax code itself, then the tax recalculated from scratch on a cumulative basis — plus National Insurance, the pension tier your pensionable pay puts you in, and your student loan plan.

Your own P60

Whether the payslips you hold add up to what your employer actually reported to HMRC. Where they do not, a payslip is usually missing.