Best Exchange Rate API for Singapore in 2026: 8 Compared for SGD Rates, MAS Data and GST

Singapore companies trade in dollars, euros, yen, ringgit and rupiah as a matter of routine, and report GST in Singapore dollars. IRAS is specific about where the exchange rate may come from and how consistently it must be used. An API that serves the Monetary Authority of Singapore table alongside live rates covers both the product and the GST return.

This comparison looks at eight exchange rate APIs from the point of view of a team in Singapore. Free-tier limits and prices were read from each provider's own pricing page on 10 November 2026; they change often, so confirm before you commit.

What a team in Singapore needs from an exchange rate API

• Live SGD pairs across Asian and major currencies.
• Monetary Authority of Singapore rates, one of the sources IRAS accepts for GST.
• A fixed, documented source: IRAS requires the chosen rate to be used consistently.
• Regional coverage: Malaysia, Indonesia, Thailand, Hong Kong and China on the same key.

Quick comparison

The Singapore rates and what they are for

• MAS exchange rates. Daily rates for 21 currencies against the Singapore dollar, described by MAS as the average of buying and selling interbank rates quoted around midday in Singapore, with weekly and monthly averages also published.
• IRAS acceptable sources for GST. Local banks, locally circulated newspapers and MAS are acceptable local sources. Reputable news agencies and foreign central banks without exchange controls are acceptable global sources.
• IRAS consistency rule. The exchange rate selected must be updated at least once every three months and used consistently for at least one year from the end of the accounting period in which the source was first used.
• Imports. Input tax on imports is claimed on the Singapore dollar amounts shown in the import permits issued by Singapore Customs.

The point for choosing an API: a market mid-rate and an official table are different products. A market rate is right for showing a customer a price. It is not the figure a tax form or an auditor asks for.

The eight providers

1. AllRatesToday

Best for: teams that need both kinds of rate. Mid-market rates for 160+ currencies refresh every 60 seconds on every plan, on any base currency, over HTTPS. The same key serves the official tables of 123 central banks and 6 tax authorities, each with the publisher's own date. For Singapore that means: MAS daily rates (21 currencies). Output is JSON, CSV, XML or Excel from the same endpoints, with SDKs for JavaScript, Python, PHP, Go and Rust and an MCP server for AI agents. Paid plans start at €4.99 a month; dated tables and history are on paid plans.

2. Frankfurter

Best for: projects that only need official fixings and want them free. Frankfurter is open source, needs no key and has no monthly cap. It now aggregates 111 central banks and official sources. For Singapore its source list covers: MAS. It serves official fixings, not a live market rate, and it is a free service with no paid tier or support contract.

3. ExchangeRate-API

Best for: dashboards and reports that need volume and can live with one update a day. The free plan gives 1,500 requests a month with daily updates; the Pro plan is $10 a month for 30,000 requests with hourly updates. Rates are a blended market figure, not a named institution's table.

4. Open Exchange Rates

Best for: teams that want a long-established vendor and work from a US dollar base. The free plan gives 1,000 requests a month with hourly updates on a USD base; other base currencies start with the $12 a month plan.

5. CurrencyAPI

Best for: small private projects. The free plan gives 300 requests a month with daily updates and is for private use only; paid plans start at $12.99 a month.

6. Fixer

Best for: teams already on the apilayer marketplace. The free plan gives 100 calls a month with hourly updates for non-commercial use, and base-currency switching is listed only on paid plans, which start at $14.99 a month.

7. currencylayer

Best for: the same apilayer stack with a dollar source. The free plan gives 100 calls a month with daily updates for non-commercial use; paid plans start at $14.99 a month.

8. XE Currency Data

Best for: banks and large companies that need a recognised vendor on an annual contract. There is a trial but no free plan; the entry plan is $599 a year for 10,000 requests a month with daily rates.

Try it for SGD

# live mid-market rate
curl "https://allratestoday.com/api/v1/rates?source=USD&target=SGD" \
  -H "Authorization: Bearer YOUR_API_KEY"

# MAS, latest table
curl "https://allratestoday.com/api/open/central-bank/mas"

# the MAS table for an invoice date
curl "https://allratestoday.com/api/v1/central-bank/mas/2026-09-30" \
  -H "Authorization: Bearer YOUR_API_KEY"

The first call needs a free API key. The official table responses carry the table's own date, so you can show which publication a figure came from.

Which one should you pick?

FAQ

What is the best exchange rate API for Singapore in 2026?

For live SGD rates plus the MAS table on one key, AllRatesToday. For MAS fixings free and without a key, Frankfurter. For the largest free quota of daily market rates, ExchangeRate-API.

Which exchange rate does IRAS accept for GST?

IRAS accepts rates from local banks, locally circulated newspapers and MAS, and from reputable news agencies and foreign central banks without exchange controls. The source must be updated at least every three months and used consistently for at least a year.

How many currencies does MAS publish?

21 currencies against the Singapore dollar, as daily rates with weekly and monthly averages.

Can I change my GST exchange rate source during the year?

IRAS requires the selected rate to be used consistently for at least one year from the end of the accounting period in which the source was first used.