---
title: "Batch-check which asset hashes already exist"
method: POST
path: "/assets/check"
---

# Batch-check which asset hashes already exist

`POST /assets/check`

Given a list of SHA-256 content hashes, returns a map of each hash to its existing asset record (or `null` if not stored in this workspace). Lets syncing clients skip the upload round-trip for content that's already been uploaded — compute the hash locally, batch-check, then only POST the missing ones to `/assets`.

Max 100 hashes per request.

## Request body

- object
  - `content_hashes` string[], required

## Response `200`

Map of `hash → asset record or null`. Keys are the hashes from the request; values are the existing asset for that hash, or null if not found.

- object

## Other responses

- `400` — Empty or oversized content_hashes array

---

[API](https://skmtc.dev/bannerbear/apis/bannerbear-v5-api.md) · [All operations](https://skmtc.dev/bannerbear/apis/bannerbear-v5-api/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/bannerbear/bannerbear-v5-api/revisions/6aa425420a10/schema)