Verified limit lookup

Cloud Firestore API Request Size

Cloud Firestore API Request Size, verified against Firebase's official documentation with scope, implementation impact, caveats, and a direct check.

Verified Aug 22, 20261 official source
Quick answer

Firebase documents maximum api request as 10 MiB. Transactions and commits also have time and transformation constraints.

Verified Aug 22, 2026Official source

Current limits

ConstraintCurrent valueScopeVerified source
maximum API requestTransactions and commits also have time and transformation constraints.10 MiBCloud FirestoreFirebaseAug 22, 2026

Why does this limit matter?

A batch with many small documents can exceed request size before reaching operation-count expectations.

This value is scoped to Cloud Firestore; a different plan, runtime, model, endpoint, region, or account can produce a different effective constraint.

What should you check?

  1. Measure serialized request bytes and split batches with idempotent retry handling.
  2. Confirm the exact plan, model, runtime, endpoint, region, and account that serve the failing workload.
  3. Record the observed value, response headers or configuration, timestamp, and source without logging secrets.

Important caveats

  • Security rules evaluation and index updates add separate constraints.
  • Treat the official source and live account configuration as authoritative if they differ from this verified snapshot.
HyperObserve reports the documented platform constraint. Your application, SDK, gateway, provider, region, or account can impose a lower effective limit.
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