66 votes
Accepted

Is there an easy way to see amount of compression in Chrome?

Updated answer for 2017: Yes. The size column in the Network tab in Chrome Developer Tools has both the compressed and uncompressed size, for gzip, brotli and whatever comes in future. Eg: Here the ...
mikemaccana's user avatar
20 votes
Accepted

Why do oversized images appear better than images that are the correct size on the web?

It's most likely due to viewing images on retina and high density screens. Before the introduction of Retina-class displays, the average screen density was far lower. Web-based images included enough ...
Pete's user avatar
  • 766
13 votes

Is there an easy way to see amount of compression in Chrome?

Update for 2017 When using large icons, the chrome dev tools show a before and after compression size in the network tabs. I confirmed by switching gzip off and on on my webserver.
CodeMonkey's user avatar
13 votes

Why do oversized images appear better than images that are the correct size on the web?

(This a basically the same as Pete's answer, just written from a different angle.) Because CSS "pixels" aren't really pixels anymore (and haven't been for quite a while). So what is a pixel,...
Ilmari Karonen's user avatar
8 votes

Why do oversized images appear better than images that are the correct size on the web?

In addition to @Pete's excellent answer, it's also possible the images you are using are overcompressed. When you scale down a large image it has more information to work with and so it can appear ...
davidgo's user avatar
  • 7,904
5 votes
Accepted

How do you serve Jekyll pages with gzip compression on GitLab Pages?

GitLab Pages will serve pre-compressed .gz files that exist alongside uncompressed equivalents. A general solution that should work with most static publishing systems is to put this as the last step ...
Daphne Preston-Kendal's user avatar
5 votes
Accepted

Why does Google mobile site test say my site is not compressed when it uses content-encoding:br?

Compress resources with GZIP This is another one of those things where new technology is being shoved into our faces and some companies and/or tools aren't setup to handle it (such as the Google page ...
Mike -- No longer here's user avatar
5 votes

Should I compress very small HTML pages?

To answer your specific question, the smallest size an HTML document (or any page asset like CSS or JavaScript) can be before compression becomes overkill will be what you can fit inside a single TCP ...
Tom Brossman's user avatar
  • 2,291
4 votes

Should I compress very small HTML pages?

Enabling compression is almost universally a good idea. You might not save much data on very small pages, but you also won't waste very much CPU compressing them. An even better idea, if you're ...
Carl Vitullo's user avatar
4 votes

What is recommended minimum object size for gzip performance benefits?

Apache Tomcat has gzip filter and it starts to zip from 2kb, my quick test tells that it's the lowest boundary, and you can increase it at least to 3-4kb. Because for 2kb you will get a similar size ...
Yura's user avatar
  • 141
4 votes
Accepted

Would compressing a PNG more than once reduce the number of colors or affect something else?

That's exactly it - the file gets smaller because the colors are combined into fewer, more prominent colors. For example, multiple shades of blue living next to each other will combine to display as ...
Henry Visotski's user avatar
4 votes

Website backup file size differs on server vs when downloaded via FTP

It isn't a virus or some sort of FTP compression. It could be a couple of things going on: For example, if the server is running Linux and your desktop is running Windows it is likely that your ...
gnicko's user avatar
  • 256
3 votes

Why does "Disable Cache" in Chrome developer tools change the "content-encoding: gzip" response header?

What does the "Disable Cache" have to do with gzip and compression? Nothing directly. Except that when "Disable Cache" is checked (ie. the local browser cache is disabled) the server is forced to ...
DocRoot's user avatar
  • 4,297
3 votes
Accepted

Is there any point to compressing HTML when using GZIP?

Your files will be smaller if you minify them before using gzip. Gzip isn't perfect compression. It doesn't remove remove all the redundancy that minifying does. Gzip is lossless compression. ...
Stephen Ostermiller's user avatar
3 votes

Why this image is so large despite small dimension

The file is suffering from something called Metadata Bloat. Basically, there's a TON of data in the "history section" of the file itself. This usually happens either because (1) the ...
I Capulet's user avatar
  • 843
3 votes
Accepted

Is it worth using next generation image formats with only partial browser support for SEO?

For the most part I think that compressing the images with higher JPG compression should suffice. I say this because we do know that Google cares a lot about speed - and the reason they are advising ...
davidgo's user avatar
  • 7,904
3 votes

can a random compression level applied on same html output replace HTTPS to an extent?

Data compressed with gzip contain all the information needed to decompress the data. This means an attacker can simply decompress the data, same as the browser. So this is no more secure than plain ...
Steffen Ullrich's user avatar
3 votes
Accepted

How to compress jpeg images for Google Page Speed Insights?

Lossless VS Normal Compression Looks like you're getting your wires mixed, Google insights refers to lossless compression, not the JPEG encoder. jpegoptim, jpegtran, jpegrescan, mozjpeg1, mozjpeg2 ...
Simon Hayter's user avatar
3 votes

Should I compress very small HTML pages?

It's a good question and there is no one size fits all answer. However with the rise of mobile networks the answer is almost always compress as much as possible. In the long run uncompressing on the ...
minusf's user avatar
  • 131
2 votes
Accepted

Enabling compression for font loaded via googleapi

This is an issue with the test, not with anything you are supposedly doing wrong. From your screen-shot I can see that the potential size savings is only 526 bytes which is well within the size of a ...
Tom Brossman's user avatar
  • 2,291
2 votes

Is there an easy way to see amount of compression in Chrome?

For anyone still arriving here from a general google search (like I did), in modern versions of Firefox it's possible to see the "raw" and gzipped size directly from its devtools by comparing the "...
LeartS's user avatar
  • 121
2 votes
Accepted

Mobile Load Time - Compressing JavaScript

To directly answer your question I would differ you to the Better Minify Plugin: https://wordpress.org/plugins/bwp-minify/ It will easily let you compress your .js files. And it will allow you to ...
MikeRapidPurple's user avatar
1 vote

What is AVIF, and why do website builders automatically convert JPEG images to it?

AVIF is an alternative image format that's related to the AV1 video codec. It has better compression efficiency and a wider feature set than earlier formats such as JPEG and WEBP. AVIF is likely ...
Maximillian Laumeister's user avatar
1 vote
Accepted

MediaWiki: Enable text compression

You can activate compression using .htaccess file if your server supports it. Just create a ".htaccess" file on your http root with this contents and run the test again: <ifModule mod_gzip.c> ...
Cristian Urrutia's user avatar
1 vote

How do I configure gzip to work on External Resources

You have no control on expires, compression or any other header property on external resources. Rather than trying to satisfy pointless speed score websites you should focus on how quickly your pages ...
Simon Hayter's user avatar
1 vote
Accepted

What image compressor Google Pagespeed Insights uses?

It's not the specific compressor you need to know here. It's actually the amount of compression that is key. Uploading images without compression will provide original quality images at a price of a ...
Mike -- No longer here's user avatar
1 vote

How to compress jpeg images for Google Page Speed Insights?

I use Gimp software plus a plugin that allows batch optimizing. The percentage of compression is the tricky part especially for batches. I would test at least one image before doing batches.
DraganAscii's user avatar
1 vote

Mobile Load Time - Compressing JavaScript

You can use plugin https://wordpress.org/plugins/bwp-minify/ And here is full detailed instruction given here http://www.wpbeginner.com/plugins/how-to-minify-css-javascript-files-in-wordpress/ ...
smarttechy's user avatar
1 vote

Sitemap compressed is in unsupported format but valid if uncompressed

I simply compressed them using gzip: gzip sitemap1.xml My server nginx is enabled to send compressed files. It looks like you're trying to send a double-compressed file and a compressed file. When ...
Mike -- No longer here's user avatar

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