Does Laravel need a separate SDK to call exchangerate.dev?

No. Laravel’s built-in HTTP client can send the bearer token, query parameters, timeout, and JSON accept header. The API returns ordinary JSON that can be handled as an array.

How long should Laravel cache an exchange-rate response?

A 60-second cache works for actively traded pairs that update about once a minute and prevents duplicate application requests from consuming the upstream limit. Check data_updated_at because a daily-reference currency can still have an older observation.

Can PHP float be used for currency conversion?

PHP float is binary floating point and can introduce representation artifacts. Use a decimal or arbitrary-precision library when exact money arithmetic matters, preserve the API rate, and round only the final display amount.

What limits apply to the free exchangerate.dev key?

The Free tier includes 10,000 calls per month at 12 requests per minute, with no card required. Cache shared reads and avoid one upstream request per page view.

Tutorial/PHP and Laravel

Exchange rates in PHP and Laravel

Fetch and cache live exchange rates with Laravel’s HTTP client, bearer authentication, bounded timeouts, and freshness metadata.

MMexchangerate.dev·Jul 17, 2026·6 min read

A small Laravel service can call exchangerate.dev, reject failed HTTP responses, and cache a complete FX observation for 60 seconds. Keep the API key in configuration and return source, market_session, and data_updated_at with the rates.

Key points

Use Laravel’s HTTP client with bearer authentication, an explicit timeout, and throw() for non-success responses.

Cache the complete successful response for 60 seconds to stay well inside the Free tier’s 12 requests per minute.

Keep the key in config/services.php through EXCHANGERATE_API_KEY, not in application code.

Use a decimal library for calculations that require exact money arithmetic; PHP floats are binary floating point.

Build one cached FX service

The service below creates a stable cache key from the base and symbol list. The callback stores only a successful JSON response because throw() raises before Laravel writes a failed request into the cache.

php · app/Services/ExchangeRateService.phpcopy

<?php

namespace App\Services;

use Illuminate\Support\Facades\Cache;
use Illuminate\Support\Facades\Http;

final class ExchangeRateService
{
    public function latest(string $base, array $symbols): array
    {
        sort($symbols);
        $symbolList = implode(',', $symbols);
        $cacheKey = "fx:latest:{$base}:{$symbolList}";

        return Cache::remember($cacheKey, now()->addSeconds(60), function () use (
            $base,
            $symbolList,
        ): array {
            return Http::acceptJson()
                ->withToken(config('services.exchangerate.key'))
                ->timeout(5)
                ->get(
                    "https://api.exchangerate.dev/v1/latest/{$base}",
                    ['symbols' => $symbolList],
                )
                ->throw()
                ->json();
        });
    }
}

Configure the key outside source control

php · config/services.php and .envcopy

// config/services.php
'exchangerate' => [
    'key' => env('EXCHANGERATE_API_KEY'),
],

// .env (never commit the real value)
EXCHANGERATE_API_KEY=exr_live_...

Read the rate and its observation fields

Call $service->latest("USD", ["EUR", "GBP"]), then read $result["rates"]["EUR"]. Keep $result["source"], $result["market_session"], and $result["data_updated_at"] in the view model or stored record so the value never loses its context.

Do not cache errors as rates

A 401 means the key or header is wrong. A 429 means the application has exceeded a request limit. Let both fail, back off where appropriate, and keep any prior successful observation only with its original update time.

Sort symbols before building the cache key.
Set a bounded HTTP timeout.
Call throw before reading and caching JSON.
Round the final amount for display, not the API rate.

exchangerate.dev

Integration guides for developers building with FX data.

Build one cached FX service

Configure the key outside source control

Read the rate and its observation fields

Keep reading