Daily Reference Rate (16:00 London)
A once-a-day, never-revised mid-market exchange rate for 160+ currencies, fixed at 16:00 London from a five-minute sampling window. Reproducible by design for index calculation, research series and reporting. Open methodology, free latest table, dated history by API.
Live mid-market rates change every minute, so two people pulling "today's rate" seconds apart get different numbers. An index level, a research series or a monthly report needs the opposite: one published value per day that anyone can look up and reproduce. The Daily Reference Rate is that value. Every business day at 16:00 London we sample our mid-market USD table once a minute for five minutes, take the median per currency, and publish the result once. It is never revised.
Latest table
No table has been published yet. The first Daily Reference Rate is due on 2026-10-12 at 16:00 London, and will appear here and at /api/open/reference-rate a few seconds after 16:02.
Methodology
- Window. Five minutes centred on 16:00 Europe/London, 15:57:30 to 16:02:30, on business days (Monday to Friday). London time is used, so the window follows UK daylight saving.
- Samples. Once a minute inside the window the full mid-market USD table (160+ currencies) is fetched live, bypassing every cache, and stored. Five samples per day is the norm; a day needs at least three to publish.
- Value. For each currency the published value is the median of its samples. The window low and high and the sample count are published alongside it, so the spread inside the window is visible.
- Coverage rule. A currency is published for a day only if it appears in at least half of that day's samples.
- Immutability. The table is written once, a few seconds after 16:02 London. It is never recomputed. Weekend and holiday lookups resolve to the previous business day and say so.
- Pairs. Any pair other than USD/x is the cross of the two USD values and is flagged
derived. The cross is exact arithmetic on published values, so it is reproducible from the table.
Method string returned with every table: median of once-a-minute mid-market samples, 15:57:30–16:02:30 Europe/London.
API
The latest table is free and keyless, with attribution. Dated tables and history use an API key; the free tier covers evaluation.
| Endpoint | Access | Returns |
|---|---|---|
GET /api/open/reference-rate | Keyless | Latest table, or one pair with ?source=&target=. ?format=csv|xlsx|xml. |
GET /api/v1/reference-rate/latest | API key | Latest table with low/high/samples. ?symbols=EUR,GBP narrows it. |
GET /api/v1/reference-rate/{date} | Paid plan | The table published on that date (or the last business day before it). |
GET /api/v1/reference-rate/history | Paid plan | One point per business day for ?symbol= or a ?source=&target= pair, from/to. |
curl "https://allratestoday.com/api/open/reference-rate?source=SAR&target=USD"{
"rate_date": "2026-10-13",
"time": "16:00 London",
"base": "USD",
"source": "SAR", "target": "USD",
"rate": 0.26664,
"derived": true, "method": "cross via USD",
"attribution": { "source": "AllRatesToday Daily Reference Rate (16:00 London)", "url": "https://allratestoday.com/reference-rate/" }
}curl "https://allratestoday.com/api/v1/reference-rate/2026-10-13?symbols=EUR,GBP,SAR,EGP" \
-H "Authorization: Bearer art_live_your_key"
curl "https://allratestoday.com/api/v1/reference-rate/history?symbol=EGP&from=2026-10-01&to=2026-12-31&format=csv" \
-H "Authorization: Bearer art_live_your_key"When to use which rate
| Need | Use |
|---|---|
| A price shown to a user right now, a checkout, a live converter | Real-time mid-market rate |
| An index level, a return series, a research dataset, a monthly report that others must be able to reproduce | Daily Reference Rate (this page) |
| A tax filing, customs declaration, VAT invoice or audit, where a rule names the publisher | Official central-bank or tax-authority rate |
| Settlement of a financial instrument that references a regulated benchmark | A registered benchmark administrator (for example LSEG's WM/Refinitiv). Not this rate. |
FAQ
Is the Daily Reference Rate the same as the WM/Refinitiv 4pm fix?
No. WM/Refinitiv (the LSEG FX benchmark) is a regulated benchmark computed from market-wide interbank trades and quotes. The AllRatesToday Daily Reference Rate is the median of our own mid-market USD table sampled once a minute in a five-minute window centred on 16:00 London. For liquid pairs the two are typically very close; for thinly traded currencies they can differ. It is not a registered benchmark.
Can I use it in an index or a published research series?
Yes. That is what it is for: one published, never-revised value per business day that your clients can look up and reproduce. Commercial plans allow derived data such as index levels and returns to be distributed; name AllRatesToday as the FX source in your methodology. It is not intended as the settlement rate of a financial instrument, which may bring the publisher under the EU or UK Benchmarks Regulation.
When is it published and is it ever revised?
Every Monday to Friday a few seconds after 16:02 London time, once the last sample of the 15:57:30–16:02:30 window is in. Values are written once and never revised. Weekend and holiday requests return the previous business day, with rate_date saying which.
Which currencies are covered?
Every currency in the real-time mid-market feed, 160+ including SAR, EGP, AED, KWD, QAR, BHD, OMR and JOD, each quoted per 1 USD. Any pair is computed as a cross through USD and flagged derived.
One reproducible rate per day, 160+ currencies
Free latest table, dated history on any paid plan. Commercial plans allow derived data such as index levels and returns to be distributed to your clients.
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