# Binary payloads

Published 24 September 2026 · Event Gateway

Binary and gzip webhooks are now supported

Hookdeck now accepts binary request bodies and delivers them to your destination byte for byte. Until now a request with a binary content type was either rejected or could get decoded as text.

Supported content types

A request is treated as binary when its `Content-Type` is a known byte-oriented format:

* `application/octet-stream`
* `image/*`, `audio/*`, `video/*`
* Archives and office documents, such as zip and PDF
* `application/protobuf`, `application/cbor`, `application/msgpack`

Requests with `Content-Encoding: gzip` or `x-gzip` are passed through as encoded bytes regardless of media type, including gzipped JSON. Event Gateway does not decompress them.

How it works

* Delivery: the destination receives the original bytes with the original `Content-Type` and `Content-Length`. Retries and replays send the same bytes.
* Raw body: fetching the raw body from the dashboard or API returns the original content type and exact byte length.
* Transformations: the body is exposed as `body: null`, but you can still transform headers, path and query.