How to Find Out AWS S3 Bucket Human Readable Size

# Download S3CMD
$ git clone https://github.com/s3tools/s3cmd.git
# Configure S3CMD
$ cd s3cmd
$ ./s3cmd --configure

$ s3cmd du s3://my-bucket
5885516953 s3://my-bucket

# Human Readable
$ s3cmd du -H s3://my-bucket
5G   s3://my-bucket

# Find All S3 Bucket Human Readable Size
$ s3cmd du -H s3://
18G      144 objects s3://bucket1/
19G      7441 objects s3://bucket2/
143G     10333 objects s3://bucket3/