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POST /eth/v1/validator/sync_committee_subscriptions

Subscribe to sync committee subnets

Join several subnets for the sync committee.

Sync committees are necessary for Altair networks but are absent from phase 0.

To enable network participation in Altair networks, VCs must subscribe to sync committee subnets. This is a necessary step only in cases where the VC has an active validator in an active sync committee.

Example Request and Result for /v1/validator/sync_committee_subscriptions

In this section, we provide an illustrative example of a request made to retrieve details contents using the /v1/validator/sync_committee_subscriptions endpoint. Additionally, we present the resulting response containing information about subscribing yo sync committee subnets.


  • none

The example in this section uses a non-existing project id.

Make sure you replace it with your Ethereum Holesky Beacon endpoint when issuing the API calls.

Don't have a project id? Here's a straightforward guide on how to obtain one!

Subscribe to sync committee subnets


Successful response

Curl Request example

curl -X 'POST' \
'<project-id>/eth/v1/validator/sync_committee_subscriptions' \
-H 'accept: */*' \
-H 'Content-Type: application/json' \
-d '[
"validator_index": "1",
"sync_committee_indices": [
"until_epoch": "1"