I want to know why events with attachments that look under Sentry’s attachment size limit are still dropped for being too large.

Sentry applies separate size limits to compressed and uncompressed attachments.

This means an attachment can be within the uncompressed limit and still be rejected if the compressed request, including the event and its attachments, exceeds the compressed limit. Oversized uploads are rejected with a 413 Payload Too Large response.

These limits can change, so check the Size limits documentation for the latest figures and your platform's attachments documentation for platform-specific details.

If you're hitting an attachment size limit, try reducing the size of the attachments, splitting large files into secondary storage, or avoiding putting bulky data directly into the event payload.

If the problem is with the event JSON itself rather than its attachments, see What can I do when my event payload is too large?