: Saving a png file for web I have a png file (with transparency) that I'd like to minimize its size for web use: https://www.dropbox.com/s/5f5utt2mttssa5v/submit2.png?dl=0 The size of the file is

@Sims5801359

I have found using an additional compression tool after saving for the web to be effective. Often results will be 20% to as much as 80% lighter than straight from Photoshop.
imageoptim.com/
(No affiliation, just a happy user!)

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@Kaufman565

There are a few things this could be.

You are embedding “Copyright and Contact info” metadata in the file. That metadata may be the source of the extra file size that you are looking for. If you want the smallest file size, do not embed any metadata.

You may be writing the metadata twice when you re-optimize. There is no point in optimizing a file that has already been optimized. What you should do is work in a master document in your editor’s native format and then you use Save for Web to export the smallest possible PNG, and you store the native document for future editing and put the PNG on the Web. The PNG you export should not be opened again for editing, it is for viewing only.

Once you have opened up your native document and exported a PNG without the metadata, you should not necessarily trust Finder to give you the right file size measurement. The 1.44 kb could include Finder metadata. If you are making a 10 megabyte file you might not notice the Finder metadata, but at the tiny size you are working at, it could be a factor. The better way to test the actual size of your file is to put it on a Web server (or possibly Dropbox) and see what the Web server says the file size is. On a Web server, it will just be the raw file, no additional Mac metadata.

Another thing to keep in mind is that there is an old way of measuring file size where a kilobyte was equal to 1024 bytes, and there is a newer standardized new way of measuring files, where a kilobyte is equal to 1000 bytes. If Photoshop is using one system and Finder (or another app) is using the other, you can see file size discrepancies. At the tiny size you are working at, the extra 24 bytes or missing 24 bytes can make a difference. That could be the discrepancy between the 456 and 582 byte files.

Also — unrelated — when you save something for the Web, you should always check “Convert to sRGB” which is the standardized RGB color space. Your PNG will be assumed to be in the sRGB color space by Web browsers and other PNG renderers. If you don’t convert to sRGB your colors will be off.

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