AI Workshop: learn to build apps with AI →
AWS: How to make your S3 buckets public

Join the AI Workshop and learn to build real-world apps with AI. A hands-on, practical program to level up your skills.


I wrote about how to upload an image to S3.

After I had the S3 bucket ready, and the image was uploaded and then the URL was stored in my database, I realized the image was not publicly accessible for reading.

The image was there, but could not be seen by anyone.

If I tried to access it, all I got was something like:

<Error>
<Code>AccessDenied</Code>
<Message>Access Denied</Message>
<RequestId>E5FBYNEYEFNZH</RequestId>
<HostId>
iImqC8XkvmPP4/BJxNGDZrPrDr7us1u3UeZqH8prlv3dk69R9m7uOaaaZDvTLAtne2rLkRWZ4=
</HostId>
</Error>

Ok, I thought, it’s a permission issue.

So first I tried to edit the “Block public access” setting, disabling the block I had:

But this didn’t work. The image was still inaccessible.

So I went and set the Everyone (public access) setting to Read in a single file permission:

and this worked, for the single file.

So I went to the general bucket permissions, which has a similar ACL permissions panel, to set the same thing.

I set Everyone (public access) setting to Read but it didn’t work as expected.

People could not see the files publicly, even though I was setting it explicitly.

It turns out there’s no way to do this through clicking around.

I had to set a Bucket Policy, which can be done from the bucket permissions page, and I added this:

{
  "Version": "2008-10-17",
  "Statement": [
    {
      "Sid": "AllowPublicRead",
      "Effect": "Allow",
      "Principal": {
        "AWS": "*"
      },
      "Action": "s3:GetObject",
      "Resource": "arn:aws:s3:::YOURBUCKETNAME/*"
    }
  ]
}

Change YOURBUCKETNAME to your bucket name.

This made it work. Once you add this, you can set the Block public access as follows:

That’s it. Now my files (images in my case) were accessible from the public.

Lessons in this unit:

0: Introduction
1: How to create an IAM user in AWS
2: ▶︎ How to make your S3 buckets public