For naming buckets in Amazon S3, the following requirements apply:
Bucket names must be three (minimum) to sixty-three (maximum) characters long.
Lowercase letters, numerals, dots (.) and hyphens are the only characters allowed in bucket names (-).
A letter or number must appear at the start and end of each bucket name.
The names of buckets must not be formatted in the form of an IP address (for example, 192.168.5.4).
The prefix xn— can't be used in bucket names.
The suffix -s3alias can't be used in bucket names. This suffix is only used in alias names for access points. Use a bucket-style alias for your access point for more details. Within a partition, bucket names have to be unique. A partition is a set of Regions that have been grouped together. AWS has three partitions at the moment: aws (Standard Regions), aws-cn (China Regions), and aws-us-gov (U.S. Government).