Twelve Data vs Finexly: Choosing a Currency API in 2026

Choosing between Twelve Data vs Finexly comes down to a single question: do you need a broad, multi-asset market data platform, or a focused, high-volume currency exchange rate API? Both deliver real-time and historical forex data over a clean JSON API, but they are built for different jobs. Twelve Data is a wide-coverage platform spanning stocks, ETFs, crypto, commodities, and forex. Finexly is a currency-first API designed for developers who need fast, reliable exchange rates and conversion without paying for asset classes they will never touch. This guide compares the two objectively on coverage, pricing, free tiers, developer experience, and performance so you can pick the right tool for your project.

TL;DR: Which Should You Choose?

If you only need currency and FX data — conversions, latest rates, historical time series — Finexly is the simpler, more cost-effective fit. Its free tier offers 1,000 requests per month with no credit card, its endpoints are currency-specific, and pricing is flat and predictable.

If you are building a trading or analytics app that needs stocks, crypto, ETFs, and forex from one provider, plus WebSocket streaming and built-in technical indicators, Twelve Data is the stronger platform. You pay for that breadth, but for multi-asset use cases it is worth it.

The rest of this article breaks down exactly where each one wins.

Quick Overview of Each Provider

Finexly is a developer-first currency API focused on real-time and historical exchange rates for 170+ currencies. It emphasizes a generous free tier, low-latency responses, and a small set of purpose-built endpoints — /latest, /historical, /timeseries, and /convert — that map directly to the things currency apps actually do. There is nothing to wade through: if your problem is "what is 1 USD in EUR right now, or on this date," Finexly is built for exactly that. You can see the full reference in the Finexly API documentation.

Twelve Data is a multi-asset financial data platform. For forex, it covers 140 currencies and precious metals that combine into over 2,000 currency pairs, updated at least once per minute. Beyond FX, it provides US and global stocks, ETFs, crypto, and commodities, along with WebSocket streaming, 20+ years of historical data, technical indicators, and SDKs for Python and other languages. Its infrastructure handles 90 million-plus requests per day and advertises a 99.99% SLA.

Feature Comparison

The pattern is clear: Twelve Data has more breadth, Finexly has more focus. If a feature only matters when you are trading equities or running technical analysis, it lives on the Twelve Data side. If your application converts money or displays exchange rates, the columns look nearly identical — except on free-tier volume and price, which we cover next.

Pricing Comparison

This is where the two diverge most, and where the right choice depends heavily on your usage pattern.

Finexly pricing

Finexly prices by monthly request volume, which suits applications that make a steady, moderate number of calls and cache aggressively:

See current tiers on the pricing plans page.

Twelve Data pricing

Twelve Data prices by API calls per minute, which suits trading and dashboard apps that poll frequently during market hours:

The structural difference matters more than the headline numbers. Finexly's monthly cap rewards caching — if you store rates and refresh them on a sensible schedule, 1,000 free requests covers a surprising amount of real production traffic. Twelve Data's per-minute model rewards burst capacity — useful when you need many symbols polled in real time, less efficient if your usage is spread thinly across the month. For a currency converter, billing engine, or e-commerce checkout, the monthly model is usually cheaper and easier to reason about. For a live trading terminal pulling dozens of instruments every second, the per-minute model fits better.

Data Coverage and Accuracy

Both providers source institutional-grade data and both are accurate enough for production. The differences are about scope:

• Currency breadth: Finexly covers 170+ currencies, slightly more than Twelve Data's 140 fiat currencies, though Twelve Data adds precious metals (gold, silver, platinum, palladium) and commodity spots like Brent and WTI within the same forex namespace.
• Pairs: Twelve Data markets 2,000+ pairs because it cross-multiplies its currency and metal list. Finexly exposes any base/quote combination across its 170+ currencies through the base and symbols parameters, which gets you the same cross-rate flexibility.
• Update frequency: Twelve Data updates forex prices at least once per minute. Finexly delivers low-latency real-time rates suited to conversion and pricing workloads. For sub-minute tick streaming of equities, Twelve Data's WebSocket is the right tool; for currency conversion, per-minute or near-real-time refresh is almost always sufficient.

If you need gold and oil spot prices alongside currencies in one feed, Twelve Data has an edge. If you need the widest fiat currency list with a clean conversion API, Finexly leads.

Developer Experience and Code Examples

Both APIs are quick to integrate. Here is the same task — getting the latest USD exchange rates — on each.

Finexly

Finexly uses simple, currency-specific REST endpoints authenticated with an API key:

curl "https://api.finexly.com/v1/latest?base=USD&symbols=EUR,GBP,JPY&apikey=YOUR_API_KEY"

In JavaScript:

const res = await fetch(
  "https://api.finexly.com/v1/latest?base=USD&symbols=EUR,GBP,JPY&apikey=YOUR_API_KEY"
);
const data = await res.json();

console.log(data.rates.EUR); // e.g. 0.92
console.log(data.rates.JPY); // e.g. 159.9

Converting an amount is a single dedicated call — no manual multiplication required:

curl "https://api.finexly.com/v1/convert?from=USD&to=EUR&amount=250&apikey=YOUR_API_KEY"

And a historical time series for charting:

import requests

url = "https://api.finexly.com/v1/timeseries"
params = {
    "base": "USD",
    "symbols": "EUR,GBP",
    "start_date": "2025-06-01",
    "end_date": "2026-06-01",
    "apikey": "YOUR_API_KEY",
}
data = requests.get(url, params=params).json()
print(data["rates"]["2026-06-01"])

Twelve Data

Twelve Data centers on a time_series endpoint and ships an official Python SDK:

from twelvedata import TDClient

td = TDClient(apikey="YOUR_API_KEY")
ts = td.time_series(symbol="USD/EUR", interval="1min", outputsize=1)
print(ts.as_json())

The raw REST equivalent:

curl "https://api.twelvedata.com/exchange_rate?symbol=USD/EUR&apikey=YOUR_API_KEY"

Both are clean. The philosophical difference: Twelve Data models everything as a symbol (USD/EUR, TSLA, BTC/USD) on a generic time-series interface, which is powerful when you mix asset classes. Finexly models base and target currencies explicitly, which is more intuitive when your entire domain is money. If you are deciding between approaches, our guide on REST vs WebSocket for currency data explains when streaming is actually worth the added complexity.

Performance and Reliability

Twelve Data publishes a 99.99% SLA and infrastructure handling 90 million-plus requests per day, with WebSocket support for high-throughput streaming — credentials that matter for trading systems. Finexly is engineered for low-latency REST responses on currency endpoints, which is the dimension that matters for conversion and checkout flows where every millisecond is added to a user's page load.

For most currency use cases, both will feel instant. The reliability question is less "who is faster" and more "what happens when the API is briefly unavailable." Regardless of provider, you should cache rates and handle errors gracefully — currency rates do not change meaningfully between requests milliseconds apart, so caching cuts cost and insulates you from outages. We cover this in depth in our post on caching and error handling best practices.

When to Choose Twelve Data

Pick Twelve Data if you:

1. Need multiple asset classes — stocks, ETFs, crypto, and commodities — from a single provider.
2. Are building a trading app or real-time dashboard that benefits from WebSocket streaming and per-minute burst limits.
3. Want built-in technical indicators (RSI, MACD, moving averages) without computing them yourself.
4. Need precious metals and commodity spot prices in the same feed as currencies.

When to Choose Finexly

Pick Finexly if you:

1. Need currency and FX data only, and do not want to pay for equities infrastructure.
2. Want the most generous free tier for currency work — 1,000 requests/month, no credit card. See the free currency API breakdown.
3. Prefer monthly-volume pricing that rewards caching over per-minute rate limits.
4. Want a dedicated conversion endpoint and the widest fiat currency list (170+) with minimal integration overhead.
5. Are a startup or solo developer who values predictable cost and a fast path from signup to first call.

You can also try the live currency converter to sanity-check rates, or compare currency APIs side by side before committing.

Migrating Between the Two

Switching is straightforward because both return JSON and both express rates as a base-to-target ratio. The main adjustments:

• Symbol vs base/symbols: Twelve Data's USD/EUR symbol becomes Finexly's base=USD&symbols=EUR.
• Conversion: replace manual amount * rate math with Finexly's /convert endpoint, or vice versa.
• Rate limits: re-tune your caching layer from a per-minute budget to a per-month budget (or back). If you cache well, this usually means fewer calls, not more.

Most teams migrating a currency-only feature off a multi-asset platform find their bill drops, because they stop paying for asset classes they never queried.

Frequently Asked Questions

Is Twelve Data or Finexly better for a currency converter? For a pure currency converter, Finexly is usually the better fit. It has a dedicated /convert endpoint, a wider fiat currency list, and monthly-volume pricing that rewards caching. Twelve Data shines when your converter is part of a larger multi-asset trading product.

Does Finexly support stocks and crypto like Twelve Data? No. Finexly is a focused currency and forex API. If you need equities, ETFs, or cryptocurrency data alongside currencies, Twelve Data's multi-asset coverage is the reason to choose it. If you only need fiat currencies, Finexly avoids the extra complexity.

Which API has a better free tier? It depends on your usage shape. Finexly offers 1,000 requests per month with no credit card, which favors apps that cache and make steady, moderate calls. Twelve Data's free Basic plan allows 8 calls per minute (800/day), which favors short, bursty testing. For a typical currency feature in production, Finexly's monthly allowance usually goes further.

Can I get historical exchange rates from both? Yes. Both provide 20+ years of historical data. Finexly exposes /historical and /timeseries endpoints designed for currency charts and backfills; Twelve Data serves history through its generic time_series endpoint. See our historical exchange rates API guide for implementation patterns.

Do I need to handle caching with either provider? Yes, regardless of which you choose. Exchange rates do not change meaningfully between back-to-back requests, so caching reduces cost, improves latency, and protects you during brief outages. It is the single highest-impact thing you can do for a production currency integration.

Ready to Try Finexly?

If your project needs reliable currency and exchange rate data without paying for asset classes you will never use, give Finexly a serious test. Get your free Finexly API key — no credit card required. Start with 1,000 free requests per month and upgrade as you grow. For a broader view of the landscape, see how Finexly stacks up against Alpha Vantage and other providers.