New Zealand dollar (NZD) exchange rate API

The New Zealand dollar – the “kiwi” in market slang – is a small economy’s currency with an outsized trading profile, popular for interest-rate differential trades and closely linked to New Zealand’s dairy and agricultural exports. Most New Zealand businesses deal heavily with Australia, so NZD/AUD is often as important as NZD/USD. The fxapi NZD exchange rate API gives you both, plus monthly averages aligned to your financial year.

NZD facts for developers

• Where it’s used: New Zealand, the Cook Islands, Niue, Tokelau and the Pitcairn Islands.
• Symbol and formatting: $, written NZ$ in international contexts. Format: $1,234.56.
• Minor unit: 2 decimals (cents). Since the 5-cent coin was withdrawn in 2006, cash totals are rounded to 10 cents.
• Central bank: the Reserve Bank of New Zealand (RBNZ), the first central bank to adopt formal inflation targeting under the Reserve Bank of New Zealand Act 1989.
• Regime: free float since 1985.
• Events in the historical data: on 16 March 2020 – the sample date on this page – the RBNZ cut its Official Cash Rate by 75 basis points to 0.25% in an unscheduled decision as the pandemic hit markets.

Get NZD rates with the fxapi API

Many New Zealand companies use a 31 March balance date, so they need averages for April–March rather than the calendar year. /v1/average (all plans, 1 request) handles any window up to 1830 days. This PHP snippet requests the CSV format and prints one line per month:

<?php
$query = http_build_query([
    'base_currency' => 'NZD',
    'currencies'    => 'AUD,USD',
    'date_from'     => '2025-04-01',
    'date_to'       => '2026-03-31',
    'period'        => 'month',
    'format'        => 'csv',
]);
$context = stream_context_create(['http' => [
    'header'        => 'apikey: ' . getenv('FXAPI_KEY'),
    'ignore_errors' => true,
]]);
$csv = file_get_contents("https://api.fxapi.com/v1/average?$query", false, $context);

if (!str_contains($http_response_header[0], ' 200')) {
    throw new RuntimeException('fxapi error: ' . $http_response_header[0]);
}

$lines  = array_map('str_getcsv', explode("\n", trim($csv)));
$header = array_shift($lines);
foreach ($lines as $line) {
    $row = array_combine($header, $line);
    printf("%s %s avg %.4f (min %.4f, max %.4f)\n",
        $row['period'], $row['currency'], $row['average'], $row['min'], $row['max']);
}

Use the averages for income and expenses and closing rates for balances – see closing vs average rates and the average exchange rates API. The PHP guide covers cURL and Guzzle, and the Australian dollar page covers the other side of the trans-Tasman pair. Translation workflows are described in accounting and financial reporting.

Things to watch

• Clipped periods. If your window starts mid-month, the first period is clipped to the span – check the days column.
• AUD/NZD direction. Confirm which way round your accountant quotes it before importing.
• Cash rounding to 10 cents applies to cash only; invoices stay to the cent.

Popular NZD pairs

Request any of these pairs – or any other combination of the 190+ supported currencies – with base_currency=NZD:

Monthly averages and fluctuation for NZD

# Monthly average NZD rates for 2025 (IAS 21 / ASC 830)
curl -G "https://api.fxapi.com/v1/average" \
  -d date_from=2025-01-01 -d date_to=2025-12-31 -d period=month \
  -d base_currency=NZD -d currencies=AUD,USD,EUR \
  -H "apikey: $FXAPI_KEY"

# How did NZD move over the last year?
curl -G "https://api.fxapi.com/v1/fluctuation" \
  -d date_from=2025-10-01 -d date_to=2026-10-01 \
  -d base_currency=NZD -d currencies=AUD,USD,EUR \
  -H "apikey: $FXAPI_KEY"

See the historical exchange rates API, average rates API and documentation for every parameter.

NZD is one of 190+ currencies in fxapi, the foreign exchange rates API for developers – live rates, daily history since 1999 and monthly averages with one API key.

Frequently asked questions