How to allow public access to a folder in S3 bucket

To make a prefix of an S3 bucket publicly readable, add the below policy to the bucket.

{                                           
"Version":"2012-10-17",                       
"Statement":                                 
[                                            
{                                             
"Sid":"publicprefix",                         
"Effect":"Allow",                             
"Principal": "*",                              
"Action":["s3:GetObject"],                      
"Resource":["arn:aws:s3:::bucketname/prefix/*"] 
}                                               
]                                               
}