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Composo runs in two fully independent production regions. Each region has its own application, API, and database, so your evaluation data stays in the region you send it to.

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Available regions

RegionLocationApplicationAPI base URL
EU (default)Frankfurt, eu-central-1platform.composo.ai (also eu.platform.composo.ai)https://platform.composo.ai
USN. Virginia, us-east-1us.platform.composo.aihttps://us.platform.composo.ai
The EU region is the default. If you signed up at platform.composo.ai and haven’t been told otherwise, you’re on EU.

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Data residency

Each region is a separate deployment with its own database, and there is no cross-region data replication. Evaluations you send to the US region are processed and stored in the US; evaluations you send to the EU region stay in the EU. This is what lets US-resident customers keep their data in the US, and EU customers keep theirs in the EU. If you have a data-residency requirement, choose the matching region when you onboard and send all traffic to that region’s endpoint.

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Choosing a region

Point the SDK or your HTTP calls at the region’s base URL. 
from composo import Composo

# EU (default) — base_url can be omitted
eu = Composo(api_key="YOUR_EU_API_KEY")

# US
us = Composo(
    api_key="YOUR_US_API_KEY",
    base_url="https://us.platform.composo.ai",
)
API keys are region-specific. A key generated in one region only authenticates against that region’s API — an EU key won’t work on the US endpoint, and vice versa. Generate a key from the region’s dashboard (platform.composo.ai for EU, us.platform.composo.ai for US) and send it to the matching base URL.

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One account across regions

Your Composo login is shared across regions, so you sign in once and can open either region’s dashboard with the same credentials. API keys, however, are issued per region (see the note above).

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Billing is unified across regions

If you run evaluations in both regions, you don’t have to add the numbers up by hand. Your /usage page shows your combined EU + US usage regardless of which region you’re viewing it from — your credit allowance, consumption, per-model breakdown, and trace-caching figures are aggregated into a single account-wide total. When a total spans more than one region, the page labels it as combined across regions. If one region’s data can’t be reached momentarily, the page still loads and shows a notice that the totals may be incomplete. See Credits and Trace caching for how usage is metered.

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Status

Regional health and incidents are published on our status page.