The IRD PAYE Calculator
Inland Revenue's PAYE calculator lives inside myIR and works out the deductions for one pay period at a time. It is the authoritative implementation and it is correct. It is built for an employer running a pay run, so it answers what must be deducted rather than what your pay is worth across a year.
Where it is, and why you may not have found it
Inland Revenue's tool is the "PAYE deductions from salary or wages calculator", reached from its Deductions from salary and wages page and opening inside myIR. Two things follow from that, and they explain most searches that end up here.
- There is no page to read. The calculator is an application, not an article. Nothing it produces is indexed, so a search engine or an AI assistant cannot quote a result from it, and neither can you link to one.
- It is scoped to one pay period. You give it a gross amount, a tax code and a pay frequency, and it returns the deductions for that period. That is exactly what an employer needs and it is not always what an employee is asking.
What each calculator is for
| IRD's calculator | This site | |
|---|---|---|
| Built for | An employer running a pay run | An employee checking a payslip |
| Scope | One pay period | Per hour, week, fortnight, month and year |
| PAYE, ACC levy, student loan, KiwiSaver | Yes | Yes |
| Employer KiwiSaver contribution and ESCT on your payslip view | Not on an employee view | Yes, per payday |
| Reachable without logging in | Inside myIR | Yes |
| Readable by a search engine or AI assistant | No | Yes, the rules are published as text |
| Authority | Definitive | Validated against IRD's own casebook |
Where the two disagree, Inland Revenue is right
This is not a comparison in which the other tool loses. Inland Revenue defines the calculation, and any calculator that disagrees with it has a bug. This site's engine exists to make the same arithmetic readable, comparable across pay frequencies, and visible to anything that cannot log into myIR. If you find a figure here that differs from Inland Revenue's, the figure here is the one to doubt, and telling us is useful.
How this engine is checked
Inland Revenue publishes a Payday Software Developers Casebook so payroll vendors can verify their calculations against worked examples with exact expected outputs. It is the nearest thing New Zealand has to an official payroll test suite.
This site's engine reproduces every row of the 2026–27 casebook, and those rows are assertions in the test suite rather than a claim in prose. One of them, computed live on this page:
| Input | Value |
|---|---|
| Weekly gross | $926.28 |
| Tax code | M |
| PAYE for the week, from this engine | $157.30 |
The same specification also fixes the details that separate a correct payslip from an approximation: Inland Revenue truncates rather than rounds, and it does so at defined points inside the pay period rather than annually. A calculator that computes an annual figure and divides by 52 will be out by cents on every payslip, which is exactly the amount people check.
Three things the period calculation does on purpose
- It annualises the period. Your pay for this period is multiplied out to a year, taxed, then divided back down. On a variable week that overshoots, which is why a heavy overtime week looks over-taxed and is settled at the end of the year.
- It does not apply the $156,641 ACC cap. The annual ACC earners' levy is capped at $2,741.22, but the period calculation charges 1.75% on the period as though the cap were not there. A high earner therefore pays more levy across the year than the cap and is squared up afterwards. This site reproduces that divergence rather than smoothing it, because the payslip is what people are checking.
- It works on the employer's obligation, not your outcome. The employer's 3.5% KiwiSaver contribution and the ESCT charged on it are real money attached to your job, and they sit outside a take-home figure.
If you have no IR330, no calculator will match your payslip
One case defeats every calculator including Inland Revenue's, because it is not a tax code in the normal sense. Without a completed IR330, your employer must deduct at the non-notified rate of 45% plus the ACC earners' levy, under code ND. If your deductions look far too high and no tax code you try reproduces them, check which code is printed on the payslip before assuming an error. See deductions from your pay.
Next
- MethodologyWhat this engine deliberately does not model
- How PAYE Is CalculatedThe calculation itself, step by step
- Official sourcesEvery figure and where it came from
- Tax code finderThe input that changes everything else
- take-home pay calculatorRun your own numbers
Common questions
Where is the IRD PAYE calculator?
It is a tool inside myIR, reached from Inland Revenue's "Deductions from salary and wages" page. It is not a public page you can link a result from, and nothing it produces is indexed.
Is the IRD PAYE calculator accurate?
Yes, it is the reference implementation. Where any calculator disagrees with it, the other one is wrong. The useful question is whether it answers your question, since it is built around a single pay period.
Why does my payslip not match a PAYE calculator?
Usually the per-period arithmetic. Inland Revenue truncates rather than rounds at defined points, so an annual calculation divided by 52 drifts by cents. The other causes are the ACC levy cap, which the period calculation does not apply, and a payroll giving credit reducing the PAYE line.
What is the Payday Software Developers Casebook?
The document Inland Revenue publishes so payroll vendors can check their calculations against worked examples with exact expected outputs. It is the closest thing to an official test suite for New Zealand payroll, and this site's engine reproduces every row of the 2026–27 edition.
Can the IRD calculator show my KiwiSaver employer contribution and ESCT?
It works from the employer's point of view, so ESCT is part of what an employer works out with it. What no take-home pay calculator does is show the employer contribution and the ESCT on your own payslip view, per payday, beside your PAYE.
Where these figures come from
2026–27 tax year (1 April 2026 – 31 March 2027). Last verified 30 July 2026.
Related
- MethodologyWhat this engine models, and what it does not
- How PAYE Is CalculatedThe formula, step by step
- Official sourcesEvery figure, and the page it came from
- Rates changelogEvery figure, and the date it changed
- take-home pay calculatorThis site's calculator