Cloud Functions version comparison

Cloud Functions offers two product versions: Cloud Functions (1st gen), the original version, and Cloud Functions (2nd gen), a new version built on Cloud Run and Eventarc to provide an enhanced feature set. This page describes new features introduced in Cloud Functions (2nd gen) and provides a comparison between the two product versions.

We recommend that you choose Cloud Functions (2nd gen) for new functions wherever possible. However, we plan to continue supporting Cloud Functions (1st gen).

New in Cloud Functions (2nd gen)

Cloud Functions (2nd gen) is Firebase's next-generation Functions-as-a-Service offering. Built on Cloud Run and Eventarc, Cloud Functions (2nd gen) brings enhanced infrastructure and broader event coverage to Cloud Functions, including:

  • Longer request processing times: Run longer-request workloads such as processing large streams of data from Cloud Storage or BigQuery.
  • Larger instance sizes: Run larger in-memory, compute-intensive, and parallel workloads.
  • Improved concurrency: Handle multiple concurrent requests with a single function instance to minimize cold starts and improve latency.
  • Traffic management: Split traffic between different function revisions or roll a function back to a prior version.
  • Eventarc integration: Native support for Eventarc triggers, bringing all 90+ event sources supported by Eventarc to Cloud Functions.
  • Broader CloudEvents support: Support for industry-standard CloudEvents in all language runtimes, providing a consistent developer experience.

See the comparison table for details.

Because Cloud Functions (2nd gen) is built on Cloud Run, Cloud Functions (2nd gen) shares resource quotas and limits with Cloud Run. See Quotas.

Comparison table

Feature Cloud Functions (1st gen) Cloud Functions (2nd gen)
Image registry Container Registry or Artifact Registry Artifact Registry only
Request timeout Up to 9 minutes
  • Up to 60 minutes for HTTP-triggered functions
  • Up to 9 minutes for event-triggered functions
Instance size Up to 8GB RAM with 2 vCPU Up to 16GiB RAM with 4 vCPU
Concurrency 1 concurrent request per function instance Up to 1000 concurrent requests per function instance


For pricing information, see Firebase pricing plans.

If you use Cloud Functions (2nd gen), you can view your costs associated with only Cloud Functions (2nd gen) as follows:

  1. Go to the Cloud Billing Reports page in the GCP Console.
  2. If prompted, select the billing account associated with your Google Cloud Platform project.
  3. In the Filters panel, under Labels, add a label filter with the key goog-managed-by and the value cloudfunctions.


Cloud Functions for Firebase (2nd gen) does not provide support for Analytics events.

Though Cloud Functions for Firebase (2nd gen) supports authentication blocking events, it does not support the same set of basic Authentication events as 1st gen.

However, because 1st gen and 2nd gen functions can coexist side-by-side in the same source file, you can still develop and deploy Analytics and basic Authentication triggers in 1st gen together with 2nd gen functions.