---
title: "A full-time salary scaled to part-time hours"
method: POST
path: "/v1/pro-rata-salary"
tags: ["Calculators"]
---

# A full-time salary scaled to part-time hours

`POST /v1/pro-rata-salary`

## Request

- Base URL: `https://api.calculate.co.nz`
- URL: `https://api.calculate.co.nz/v1/pro-rata-salary`
- Auth: API key in header `X-API-Key`

What a full-time salary is worth at fewer hours, gross and after tax.

The gross part is a proportion, and the useful part is what follows it: the
take-home does not scale with the hours, because dropping to half time
drops the salary out of the higher brackets. Someone going from full time
to three days often keeps more than 60% of their take-home, and that is the
number the decision actually turns on.

`hourly_rate` is the full-time salary over full-time hours times 52, which
is the rate the job pays. Dividing the pro rata salary by the pro rata hours
gives the same figure.

The Independent Earner Tax Credit defaults on, because part-time earnings
are exactly the band where it is worth the most. Turn it off for someone on
a main benefit, Working for Families or NZ Super.

## Request body

- ProRataRequest
  - `full_time_salary` number, required: The advertised full-time annual salary.
  - `full_time_hours` number: Hours a week the full-time role is based on.
  - `your_hours` number: Hours a week actually worked.
  - `kiwisaver_rate` number: Employee contribution as a DECIMAL.
  - `has_student_loan` boolean: Whether repayments are deducted.
  - `claim_ietc` boolean: Whether the Independent Earner Tax Credit applies. Part-time earnings are exactly where it is worth the most, so it defaults on.

## Response `200`

Gross at the reduced hours, and the take-home the website does not show.

- ProRataResponse
  - `result` ProRataResult, required
    - `full_time_salary` number, required: Full-time salary as given.
    - `full_time_hours` number, required: Full-time hours a week.
    - `your_hours` number, required: Hours a week worked.
    - `fraction_of_full_time` number, required: Hours as a percentage of full time.
    - `pro_rata_annual` number, required: The salary at those hours, gross.
    - `hourly_rate` number, required: Implied hourly rate, from the full-time salary over full-time hours times 52. The same number either way round.
    - `monthly` number, required: Gross a month.
    - `fortnightly` number, required: Gross a fortnight.
    - `weekly` number, required: Gross a week.
    - `take_home_annual` number, required: After PAYE, ACC, KiwiSaver and student loan.
    - `take_home_weekly` number, required: Take-home a week.
    - `income_tax` number, required: PAYE income tax on the pro rata salary.
    - `acc_levy` number, required: ACC earner levy.
    - `kiwisaver_employee` number, required: Employee KiwiSaver contribution.
    - `student_loan` number, required: Student loan repayment.
    - `tax_year` string, required: Tax year the rates are for.
  - `disclaimer` string, required: Scope and limits of this calculation.

## Other responses

- `422`: Validation Error

---

[API](https://skmtc.dev/calculate/apis/calculate-co-nz-api.md) · [All operations](https://skmtc.dev/calculate/apis/calculate-co-nz-api/llms.txt) · [OpenAPI document](https://skmtc.dev/calculate/apis/calculate-co-nz-api/revisions/aa59a8e76614?raw)