Limits
| Item | Limit |
|---|---|
| Bucket name | 3 to 63 characters: a-z, 0-9, -, .; starts and ends with a letter or digit; no .. |
| Object key | 1,024 bytes, 64 /-separated levels; no ., .. or empty segment (a single trailing / is allowed). A key cannot also be the "folder" of another key (a and a/b) |
| Object size | No limit other than the quota and the disk: bodies are streamed |
User metadata (x-amz-meta-*) | 2 KiB in total |
Stored headers (Content-Type, Cache-Control, Content-Disposition, Content-Encoding, Content-Language, Expires) | 8 KiB in total |
| Multipart | Part numbers 1 to 10,000; no part size limit; unfinished uploads deleted after S3_UPLOAD_TTL (24 h) |
| Listing | 1,000 keys per page |
| Request bodies | Bucket policy 20 KiB; CORS and encryption configuration 64 KiB; ACL 16 KiB; versioning configuration 4 KiB; CompleteMultipartUpload 10 MiB; admin API 64 KiB |
| Presigned URL | 1 second to 7 days |
| Clock skew | 15 minutes |
| Request headers (HTTP/1) | Received within 30 seconds |
| Idle new connection | Closed after 30 seconds without a byte |
| Upload body | Aborted after 60 seconds without data, or under S3_MIN_UPLOAD_RATE (4096 bytes/s) over 60 seconds |
| Connections | S3_MAX_CONNECTIONS (1024) |
| HTTP/2 | Ping every 30 seconds, dropped after 20 seconds without answer; 128 streams per connection |
aws-chunked chunk header | 4,096 bytes |
| Encryption chunk | 1 MiB; each chunk adds 16 bytes on disk |
Over a size limit, the server answers 413 EntityTooLarge.