# Document too large
Full text: `BSONObjectTooLarge` or `document too large`. MongoDB caps a single document at 16MB. There is no option to raise it.
## Confirm
Check which write path creates the giant: unbounded arrays (event logs, comments, history appended forever), embedded base64 blobs, or denormalized copies that grew.
## Fix, pick one
- Chunk the array into separate documents (one document per page of N items, or one document per array element with a parent reference).
- Store blobs in GridFS or object storage and keep only a pointer in the document.
- Reference instead of embed for unbounded one-to-many relationships.
## Verify
Insert the previously failing payload through the new shape. Also add a guard: validate array length or payload size in application code so the next growth spurt fails fast with your error, not the driver's.