Quick answer
UniRateAPI - UniRateAPI wins for most builders because its free tier is much larger, includes more asset coverage, and gives a cheaper path to paid usage if you need historical data.
How the free tiers compare
These two free tiers are aimed at the same kind of builder, but they optimize for different problems. Abstract Exchange Rate API gives you a small, steady quota with live and historical currency data in the free plan, plus a strict 1 request/second limit. It is the better fit if you need a simple REST currency API and want to stay under a modest monthly cap without a card. UniRateAPI’s free tier is broader for testing and small apps: 200 requests/day, 170+ fiat currencies, 420+ cryptocurrencies, real-time rates, conversion, and EU VAT rates. The tradeoff is sharper: historical data is blocked on free. On the paid side, Abstract jumps to a much pricier $99/month plan, while UniRateAPI starts at $9/month, so the cost gap widens fast once you outgrow free.
Abstract Exchange Rate API vs UniRateAPI free tier, side by side
| Abstract Exchange Rate APIFTV 50 | UniRateAPIFTV 52 | |
|---|---|---|
| Free requestsA uses a monthly cap; B uses a daily cap with a higher effective monthly allowance. | 500 requests/month | 200 requests/day (6,000/month) |
| Rate limitB's input does not provide a free-tier requests-per-second limit. | 1 request/second | Not stated |
| Historical data in free tierB explicitly says no historical data access on free. | Included | Not included |
| Currency coverage in free tierA's input does not specify the number of supported currencies. | Not stated | 170+ fiat currencies, 420+ cryptocurrencies |
After you outgrow the free tier
Abstract uses flat pricing, with the first paid plan at $99/month for 60,000 requests/month and 3 requests/second, then custom enterprise pricing after that. UniRateAPI is also flat-priced, but its first paid plan is only $9/month and adds much higher daily limits plus historical data. For a small team that just needs to move past free, UniRateAPI stays far cheaper. Abstract becomes a bigger jump in cost, and the input does not provide any lower intermediate plan between free and Standard.
Cost at real usage
| Usage | Abstract Exchange Rate API | UniRateAPI |
|---|---|---|
| 500 requests/monthB's free tier is larger than this usage. | Free (within tier) | Free (within tier) |
| 6,000 requests/monthThis is the monthly equivalent of B's daily cap. | Over free tier, no rate given in input | Free (within tier) |
| 60,000 requests/monthA's Standard plan explicitly includes 60,000 requests/month. | $99/mo | Over Pro Tier limit, no higher paid price given in input |
Estimates, not quotes. Usage-based rates change - verify with the vendor's pricing page before committing.
When to pick each one
Pick Abstract Exchange Rate API when…
- You only need a few hundred currency lookups per month and can stay within 500 requests/month.
- You want live and historical currency data in the free tier without adding a card.
- You prefer a simple monthly cap over a daily quota and do not need very high throughput.
- You are building a small internal tool or prototype that makes occasional exchange-rate checks.
Pick UniRateAPI when…
- You need a much larger free allowance for testing, at 200 requests/day.
- You want access to 170+ fiat currencies and 420+ cryptocurrencies from the free plan.
- You need real-time exchange rates, currency conversion, and EU VAT rates without paying.
- You expect to outgrow free soon and want a much cheaper first paid tier.
- Historical data matters and you are fine paying for it once you move past free.
Bottom line
For the most common builder case, UniRateAPI is the better free-tier choice. It gives you far more room to experiment, broader asset coverage, and a much cheaper first paid step when you need to scale. Abstract Exchange Rate API is the cleaner pick if you specifically want historical data in free and can live with a small monthly quota. But once you expect meaningful production usage, UniRateAPI is easier to justify on cost.
Read the full listings: Abstract Exchange Rate API and UniRateAPI. Scores use the FTV methodology at /ftv. Browse more head-to-heads on /compare, or see the top-ranked free tiers on /top.