New Zealand money calculators that connect pay to after-tax decisions
Add or remove GST for a standard-rated price, see what reaches your bank account, compare a cash decision after RWT and PIR, carry salary into KiwiSaver, then test either a first-home withdrawal or retirement income. GrowThenDraw keeps tax rates and assumptions visible instead of hiding them inside one unexplained number.
What are you trying to decide?
Add or remove GST
Convert standard-rated prices between GST-exclusive and GST-inclusive totals, with quantity, discount and a visible calculation audit.
Calculate GST →Understand take-home pay
Estimate PAYE, ACC earners' levy, KiwiSaver and student-loan deductions by pay period using current New Zealand rules.
Start with PAYE →Compare cash after tax
Compare a quoted term-deposit rate after RWT with a term or cash PIE after PIR, including the break-even PIE rate and opening DCS headroom.
Compare deposit and PIE →Build a first-home deposit
Carry salary into KiwiSaver, check the three-year membership boundary and combine an eligible withdrawal with outside cash savings.
Plan a first home →Turn savings into retirement income
Bridge any years before 65, add KiwiSaver and the current NZ Super rate, then stress-test a weekly income target through later life.
Plan retirement income →Pick the calculation you need
Each page states its assumptions, important exclusions and the date its local rules were checked.
GST calculator
Apply New Zealand's 15% standard rate, see exclusive, GST and inclusive values, and export or share the exact calculation.
Open calculator →PAYE and salary calculator
Estimate take-home pay by pay period and compare how KiwiSaver rates change employee cash and employer contributions.
Open calculator →Term deposit and PIE calculator
Compare visitor-entered offers after tax, audit interest crediting and check opening protected-deposit headroom without a provider ranking.
Open calculator →KiwiSaver calculator
Model employee and employer contributions, ESCT, government contribution eligibility, a first-home withdrawal and the long-run balance.
Open calculator →Retirement income calculator
Solve accessible savings needed at retirement, add KiwiSaver at 65, apply the selected 2026 NZ Super rate and test a lower real return.
Open calculator →Move from saving to withdrawal or debt decisions without hunting through an unrelated directory.
Calculation stages, assumptions and exclusions stay beside the answer instead of being hidden in fine print.
Share links, CSV and print/PDF work without an account, email address or lead form.
New Zealand guides
How to calculate GST in New Zealand: add, remove and check 15% GST
Use the right formula for an exclusive or inclusive price, check the GST component and understand when a simple 15% calculation is not enough.
Term deposit vs PIE in New Zealand: compare what remains after tax
Work from the rate you were offered, apply RWT or PIR correctly, compare after-tax maturity values and confirm DCS protection for the exact product.
How to connect NZ Super, KiwiSaver and a retirement income target
Separate pre-65 bridge savings from KiwiSaver, use the correct NZ Super situation and test whether a weekly target survives a lower real return.
KiwiSaver contribution rates in 2026: what changed and what comes next
Follow the 3.5% employee and employer minimum, available rate choices, temporary reduction and scheduled 4% increase.
KiwiSaver ESCT and government contribution: the 2026 numbers
See why the gross employer percentage is not the amount invested and how the $260.72 government maximum is earned.