1 Best APIs for USD Base Currency (free plan) in Nigeria

CurrencyLayer is one of the most widely-used and long-established exchange rate APIs in the world, providing real-time and historical foreign exchange data for 168 currencies and precious metals. Now owned and operated by APILayer — a platform aggregating developer APIs across multiple categories — CurrencyLayer benefits from enterprise-grade infrastructure, high availability, and a large developer community built up over years of operation. Nigerian Naira (NGN) is fully supported as both a source and target currency. **What CurrencyLayer Does** CurrencyLayer delivers exchange rate data sourced from banks and commercial data providers, providing accurate mid-market rates for 168 world currencies alongside precious metals including gold (XAU), silver (XAG), platinum (XPT), and palladium (XPD). The API supports real-time rate queries, historical rate lookups for any past date, and currency conversion calculations. All responses are delivered in JSON format via simple HTTPS GET requests. **Nigeria Support** NGN (Nigerian Naira) is one of 168 supported currencies. On paid plans (Basic and above), NGN can be used as the base currency — allowing Nigerian apps to fetch NGN-denominated rates for all other currencies in a single call. On the free plan, the base currency is locked to USD (developers can still get NGN rates but must calculate conversions from the USD base). **Authentication** API access requires an API key, which is appended to all request URLs as the access_key query parameter (e.g., ?access_key=YOUR_KEY). API keys are issued immediately upon free signup at currencylayer.com. The service uses HTTPS for all requests to protect key confidentiality. **Pricing Plans** CurrencyLayer offers five tiers: - **Free**: 100 API calls/month, USD base currency only, hourly update frequency - **Basic**: $13.99/month — 10,000 calls/month, all 168 base currencies, conversion endpoint - **Professional**: $52.99/month — 100,000 calls/month, 10-minute rate updates - **Professional Plus**: $84.99/month — 500,000 calls/month, 60-second rate updates - **Enterprise**: Custom pricing for very high volume requirements The critical limitation of the free plan is the USD-only base currency restriction. Nigerian developers who need NGN as a base currency (e.g., to display NGN/USD rather than USD/NGN) must upgrade to at least the Basic plan ($13.99/month). **Update Frequency** Like ExchangeRate-API and other tiered providers, CurrencyLayer's rate freshness scales with plan: - Free and Basic: Updated every 60 minutes - Professional: Updated every 10 minutes - Professional Plus: Updated every 60 seconds For production Nigerian fintech applications requiring near real-time accuracy, the Professional Plus plan's 60-second updates are appropriate. **Historical Data** Historical exchange rate data is available on paid plans, enabling developers to query the exact NGN exchange rate on any specific past date. This is critical for Nigerian businesses that need to record foreign-currency transactions at the exchange rate prevailing on the transaction date — a requirement under IFRS accounting standards used by many Nigerian companies. **Precious Metals** CurrencyLayer is one of the few exchange rate APIs that includes gold and silver prices in its currency list. Gold (XAU) and silver (XAG) prices are returned in the same API response as fiat currencies, making CurrencyLayer useful for Nigerian commodity investment platforms and jewellery businesses that need to track both precious metal values and NGN FX rates. **APILayer Ecosystem** As part of the APILayer product suite, CurrencyLayer users can manage their API key, view usage analytics, and access support through the APILayer dashboard. APILayer also offers complementary APIs (VAT rates, IP geolocation, etc.) that can be purchased and managed in the same account — convenient for developers building multi-feature financial applications. **Important Limitation for Nigeria** CurrencyLayer provides official mid-market exchange rates from banks and data providers. It does not provide Nigerian parallel market (black market) or Bureau de Change rates. In periods of significant Naira volatility or divergence between official and parallel rates, CurrencyLayer rates may not reflect what Nigerian consumers or informal businesses actually transact at. For parallel market tracking, use Monierate. **Comparison with ExchangeRate-API** CurrencyLayer is older and more widely deployed but has a more restrictive free tier (100 calls vs. 1,500 calls on ExchangeRate-API). The Basic plan at $13.99/month is more expensive than ExchangeRate-API Pro at $10/month for comparable features. CurrencyLayer's advantage is the inclusion of precious metals and the APILayer ecosystem. Choose CurrencyLayer if precious metals rates or APILayer ecosystem integration matter; choose ExchangeRate-API for a more generous free tier and lower entry-level paid pricing. **Frequently Asked Questions** Q: Can I use NGN as a base currency on the free plan? A: No. The free plan is locked to USD as the base currency. Upgrade to Basic ($13.99/month) for NGN base currency support. Q: Does CurrencyLayer include gold prices? A: Yes. Gold (XAU), silver (XAG), platinum (XPT), and palladium (XPD) are included in the 168-currency response. Q: How do I authenticate API requests? A: Append your API key as access_key=[YOUR_KEY] in the request URL query string. Q: Is there a sandbox for testing? A: No dedicated sandbox — testing uses the live API with free tier credentials. Q: Who owns CurrencyLayer? A: CurrencyLayer is owned by APILayer, a platform aggregating developer-focused APIs.