--- title: "Data Sources: Open Exchange Rates' Blended Feed vs AllRatesToday's Institutional Market Data" description: "Open Exchange Rates blends rates from undisclosed sources. AllRatesToday publishes its sources: institutional foreign exchange market data. Here's why that transparency matters for compliance and accuracy." canonical: https://allratestoday.com/blog/openexchangerates-data-sources-vs-allratestoday/ source: AllRatesToday (https://allratestoday.com/) — Markdown mirror of the page above; index of all pages at https://allratestoday.com/llms.txt generated: 2026-10-27T14:04:54.398Z --- ![Financial data sources](https://images.pexels.com/photos/4651145/pexels-photo-4651145.jpeg?auto=compress&cs=tinysrgb&dpr=2&h=650&w=940) When your product touches money, "where does the rate come from?" is a question your risk, compliance, or audit team will eventually ask. If the answer is vague, the conversation gets expensive. Open Exchange Rates describes its data as: *"collected from several reliable sources and blended together algorithmically... other sources are not currently disclosed, but providers are monitored closely and routinely checked."* That's a reasonable description for a consumer-facing product. For a regulated environment, it leaves gaps. **AllRatesToday** publishes its sources explicitly: **institutional foreign exchange market data**. This article explains why that transparency matters, what the practical accuracy difference looks like, and when it actually affects your decision. ## The two approaches ### Open Exchange Rates: blended, undisclosed From their FAQ and documentation: - Data is aggregated from multiple sources. - The specific providers are not disclosed publicly. - Providers are monitored internally. - Rates aim to be "consistent and unbiased, providing the most representative market rate possible — generally the midpoint between the most common buy/sell prices." - They note rates "are accurate enough for 99% of cases (shopping carts, personal finance, estimates, etc.)." For most web apps, this is fine. For a regulated fintech or a public company's accounting close, the audit trail stops at "a blend." ### AllRatesToday: named, publicly disclosed Sources: - **institutional foreign exchange market data** — the institutional FX data feed used by banks, asset managers, and trading desks. - **Interbank market feeds** — the rates at which banks transact with each other. Same mid-market rate philosophy: no bank markup, no retail spread, just the midpoint between buy and sell in the institutional market. ## Why sourcing transparency matters ### Compliance and audit - **SOX (US public companies):** auditors ask how revenue denominated in foreign currencies was translated. "Blended from undisclosed sources" is a weak answer. - **IFRS / GAAP reporting:** exchange rate disclosures in financial statements often require naming the source. - **SOC 2 / ISO 27001:** service organization controls ask about data provenance for inputs to pricing and billing. - **FX-regulated industries (remittance, payments, broker-dealer):** regulators care whether your rate source is reproducible and independently verifiable. A stated rate type (mid-market, no markup) with a timestamp on every response is easy to describe in an audit memo. For figures an auditor must reproduce exactly, use an official central-bank rate. ### Accuracy under stress Blended feeds average out discrepancies between sources. That can be good (no single outlier dominates) or bad (a real move gets smoothed before it propagates). A feed refreshed every minute follows intraday market moves closely, while an hourly snapshot can miss them. In calm markets, the two approaches produce nearly identical numbers. In volatile markets — central bank announcements, macro surprises, geopolitical events — a minute-level feed shows the move within a minute, an hourly one up to an hour later. ### Reproducibility If a customer disputes a rate ("you charged me at 0.923 but the market was at 0.925 at that time"), you need to point them at a source they can verify. A named feed makes that trivial; a blended feed makes it a judgment call. ## When the difference doesn't matter - Price display for informational purposes ("USD/EUR is roughly 0.92 today"). - Shopping carts where rates are hedged through a payment processor (the processor's rate is what actually applies). - Analytics dashboards where accuracy to within 5-10 basis points is fine. - Non-regulated use cases where no one will ever ask for source documentation. ## When the difference matters - Anywhere the rate is the *contractual* conversion rate (remittance, cross-border invoicing, settlement). - Audited financial reporting. - Regulated industries (fintech, broker-dealer, payments). - Backtests where you want the most realistic intraday behavior. - Any case where a customer or auditor could demand source documentation. ## The data-pipeline picture ### OpenExchangeRates (inferred from public descriptions) ``` [Undisclosed Source A] ──┐ [Undisclosed Source B] ──┤ [Undisclosed Source C] ──┼──> Blending algorithm ──> latest.json (updated hourly) [Undisclosed Source N] ──┘ ``` Opacity: which sources, how many, what weights, what rejection rules. ### AllRatesToday ``` Institutional FX market data ──┐ Market data feeds ─────────────┼──> Mid-market aggregation ──> /api/v1/rates (updated every 60s) ``` Transparency: sources named, philosophy stated (mid-market), cadence documented. ## How to evaluate your own situation Ask these questions about your use case: 1. **Will anyone ever ask where this rate came from?** (Auditor, regulator, customer, internal finance team.) 2. **Is the rate the contractual amount?** (Vs. a display-only reference.) 3. **Does my industry have rules about FX data provenance?** (Payments, remittance, insurance, broker-dealer.) 4. **Do I need the freshest possible rate during volatile sessions?** (Trading-adjacent, treasury, hedging.) One "yes" = sourcing transparency matters enough to choose a named-feed provider. No "yes"es = blended is fine. ## The practical test Run both providers side-by-side for a month and log the delta on major pairs during volatile days (US CPI release, ECB meeting, BoJ intervention). You'll see: - Calm day: delta <5 bps most of the time. - Volatile hour: delta can reach 20-50 bps as OpenExchangeRates' hourly cadence lags a minute-level feed. For most apps, 5 bps on a calm day doesn't matter. For any app where the rate is the contractual amount, a 30-bp gap during volatility does. ## Named, auditable sources institutional foreign exchange market data feeds, 60-second updates, named and auditable sources. No credit card. [Get your free API key](https://allratestoday.com/register/) ## Related Articles - [Where Does Exchange Rate Data Come From?](https://allratestoday.com/blog/where-does-exchange-rate-data-come-from/) - [OXR Hourly vs Real-Time Updates](https://allratestoday.com/blog/openexchangerates-hourly-updates-vs-realtime/) - [Migrate from Open Exchange Rates](https://allratestoday.com/blog/migrate-from-openexchangerates-to-allratestoday/)