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POST
Create an upload

Authorizations

Authorization
string
header
required

Bearer authentication header of the form Bearer <token>, where <token> is your auth token.

Body

application/json
contentType
string
required

The MIME type of the file to upload. Supported types are image/jpeg, image/png, image/gif and image/webp.

Example:

"image/png"

contentLength
integer
required

The size of the file in bytes. Must be a positive integer no greater than 4,000,000 bytes.

Example:

102400

Response

Pre-signed upload URL created.

emailAssetId
string
required

The ID of the created asset. Pass this as emailAssetId to POST /v1/uploads/{emailAssetId}/complete once the file has been uploaded.

Example:

"cla3s5s7e9t1i3d5f7g9h1j3"

presignedUrl
string
required

The pre-signed URL to upload the file to with an HTTP PUT request. Send the same Content-Type and Content-Length used in the create request.

Example:

"https://loops-assets.s3.amazonaws.com/uploads/cla3s5s7e9t1i3d5f7g9h1j3?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=..."

Last modified on July 20, 2026