You can check if Transfer Acceleration is enabled on your bucket using the AWS CLI or SDKs, and then perform a transfer speed test.
AWS CLI to check the status:
aws s3api get-bucket-accelerate-configuration --bucket my-bucket
Output should indicate:
{
"Status": "Enabled"
}
Transfer Speed Test: AWS provides a built-in tool to test the speed improvement:
aws s3 transfer --bucket my-bucket --key test-file.txt --file local-test-file.txt