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Bar chart of file sizes for a photo at four print sizes, 8x10 to 24x36. PNG bars run from 11.3 to 70.6 MB and JPEG bars from 1.4 to 6.5 MB, with a dashed line at Etsy's 20 MB limit.

How many pixels does an AI print need? 300 per inch, and at 16x20 our PNG is over Etsy's download limit

The usual answer is 300 pixels per inch of print: 2400 x 3000 for an 8x10, 4800 x 6000 for a 16x20, 7200 x 10800 for a 24x36. A square Midjourney 8.2 HD image is 2048 x 2048 and a square Gemini 4K image is 4096 x 4096, so neither reaches a 16x20 at that rate without more pixels. (Shops write DPI. Here it means pixels per inch of print.) From a 4K Gemini picture we made 16x20 files of 4800 x 6000 pixels: the PNG is 35.8 MB, over Etsy's 20 MB per file for digital downloads, and the JPEG is 3.6 MB.

Nov 6, 2026 7 min read

Two rows of seven squares, one per test post. After the default wp media regenerate, four squares are red and read 404 and three read 200; after --skip-delete and the rewrite, all seven read 200.

Convert your existing WordPress images to WebP without a plugin: what regenerate breaks

On a WordPress 7.1.4 test site, one filter and wp media regenerate turned the resized copies WordPress makes of five full-colour (4:4:4) photographs into WebP files with 62.5% of the JPEG copies' bytes. All 25 WebP copies, five sizes of each photograph, also scored lower. The filter and regenerate also left four of our seven test posts pointing at copies WP-CLI had just deleted, and took the srcset off all seven inserted images that had one. The version below leaves no address broken and gives six of those seven their srcset back: the filter, regenerate with one flag, and a rewrite that changes an address only where a WebP exists. The recipe as printed needs WP-CLI and a shell on the server.

Nov 5, 2026 8 min read

Four teal circles on a transparent background, above the same image converted to JPG with Pillow, where the strips behind them came out magenta, white, black and black.

Why does a transparent PNG turn black as a JPG? The colour hiding underneath

We made an 800x400 test PNG with four strips that look alike: the same teal circle on a transparent background, four times over (the fourth with a soft shadow). Then we turned it into a JPG with Pillow, Python's imaging library, using its convert("RGB"). The four strips came back magenta, white, black and black. Nothing was added. Those colours were already in the PNG, sitting under the transparency. A JPG can't store transparency, so whatever writes it has to put something behind the picture. Some tools paint white. Some just reveal the colour stored under the transparent pixels, which is often black. And Chrome's canvas, the drawing surface web pages use to edit images, paints black whatever was there, because the HTML standard says it must. If you want white, or any other colour, you have to choose it before the JPG is written. Iminify's JPG output puts white behind the picture, and PNG to WebP keeps the transparency instead.

Nov 2, 2026 8 min read

Ten squares: 4 filled for tools that kept the IPTC AI tag at their defaults, 6 hollow for tools that dropped it, beside the title Does compression remove the AI tag?

Does compression remove the AI tag Merchant Center asks for? 10 tools, WordPress and Iminify tested

Google's Merchant Center help says: "Don't remove embedded metadata tags such as trainedAlgorithmicMedia from such images. All AI-generated images must contain the IPTC DigitalSourceType trainedAlgorithmicMedia tag." (Merchant Center's help page is dated February 2024; we read it on 26 October 2026.) So we put that tag on two AI images, a harbour scene from Nano Banana 2 (a JPEG) and a bakery illustration from the original Nano Banana (a PNG), ran them through 42 command-line runs and Iminify, added three larger JPEGs for a WordPress 7.1.3 site, and read the tag back with ExifTool each time. Each tool's default decides whether the tag survives, and neither lossy nor lossless predicts it. Of the ten tools in our table, four keep the tag at their defaults and six drop it, and for nine of them we found an option that flips that. Iminify, which is our product, lost it at every level that compresses: it survived in 6 of 51 uploads, and those six came back byte for byte unchanged. One ExifTool command puts the tag back for 514 to 568 bytes and, on the nine files we checked, leaves every pixel alone.

Oct 30, 2026 8 min read

Two cards for the same photograph: the JPEG saved at quality 80, 449 KB, score 75.6, and the WebP made from it at quality 90, 531 KB, score 71.3.

Why is my WebP bigger than the JPG? Measured on 40 JPEGs and 4 PNGs

One photograph of our corpus, the Fjord, saved as a JPEG at quality 80 weighed 449,258 bytes. Converted to WebP at quality 90, it weighed 531,474, which is 18% more. Scored against the corpus master it came from (a JPEG saved at quality 92), the bigger file was also the worse picture: 71.3 on SSIMULACRA 2, a score where higher means closer to the master, against 75.6 for the JPEG. Google's WebP FAQ says a WebP can grow larger than its source and names three situations. We measured each on five photographs and four graphics. A WebP comes out bigger when its quality is set too high for the JPEG it came from, when it is lossless, or when a PNG already squeezed to 256 colours goes to lossy WebP. A fourth cause, which the FAQ doesn't list, is that WebP isn't always smaller than a good JPEG even at the same score. Whichever it is, keep the smaller file when the two look alike.

Oct 29, 2026 7 min read

Two white cards on a blue gradient: WebP at quality 75, 35.1 KB, score 68.0, and AVIF at quality 47, 25.5 KB, score 68.8, beside the headline "A quality of 75 ships as WebP 75, or AVIF 47 if enabled".

What image quality does Next.js ship? WebP 75, AVIF 47 if you list it, and by default a 90 becomes 75

We built a Next.js 16.4.3 app with four images on one page, two of them declared with quality={90} and quality={100}. All 36 image addresses in the page's HTML said q=75. We also asked the image endpoint for q=90 directly, and it answered HTTP 400: "q" parameter (quality) of 90 is not allowed. That is Next 16's default: the list of allowed qualities is [75], and the component moves anything else to the nearest entry. This post follows the 75 to the encoder, in WebP and in AVIF if you switch it on, across 867 requests to a self-hosted /_next/image on nine source images. The default WebP puts one of our five photographs at 1080 px above 70, the "high quality" mark on SSIMULACRA 2, a perceptual score. AVIF at the same setting was 36.5 percent smaller across our 27 image and width combinations, and more than 3 points below WebP on score in 8 of them.

Oct 27, 2026 7 min read

Two enlarged crops of the same red text saved as JPEG at quality 80, one at 4:2:0 and one at 4:4:4, beside the title. The 4:2:0 crop has a duller, browner red.

Why is red text blurry in JPG and WebP? Chroma subsampling, measured

On a test page we made full of red text, no quality from 30 to 100 lifted a plain 4:2:0 encode (no -sharp_yuv) past 58.2 on the SSIMULACRA 2 scale, which runs to 100: JPEG (cjpegli) reached 57.9, WebP 55.2, AVIF (avifenc) 58.2. The same JPEG written at 4:4:4 scored 81.6 at quality 90. That gap is chroma subsampling: 4:2:0 keeps colour at a quarter of the detail that brightness gets, and 4:4:4 keeps all of it. It's why red text looks blurry in a JPG or a WebP. The fix is 4:4:4 for JPEG and AVIF, -sharp_yuv for lossy WebP (which narrows the gap), or lossless WebP on a flat page; What we'd use has the numbers and commands.

Oct 26, 2026 6 min read

Bar chart of what Squarespace sent for 1,000-pixel copies: 368 JPG uploads came to 41.8 MB of WebP for Chrome against 55.1 MB of JPEG without WebP; 101 PNG uploads to 36.5 MB of lossless WebP against 17.1 MB of palette PNG.

Does Squarespace compress images? What it sent Chrome for 621 images

Yes. On 25 September 2026 we asked Squarespace's image server for 621 images from 85 Squarespace sites, once the way Chrome asks and once the way a browser without WebP support asks. On 84 of those sites Chrome got a WebP that Squarespace had made itself, for every JPG and PNG upload. Squarespace's resized JPEG copies were encoded at quality 85, its WebPs came closest to quality 85 of the settings we tried, and none of the 35 uploads wider than 2,500 pixels came back wider. At 1,000 pixels wide, Chrome's WebPs of JPG uploads weighed 24% less in total than the JPEG copies Squarespace sends browsers without WebP. Chrome's WebPs of PNG uploads were lossless and weighed more than twice as much as the PNG copies those browsers get, cut to 256 colours or fewer. GIFs went out as GIFs. What that means for your uploads is in the list near the end.

Oct 19, 2026 8 min read

Three c2patool verdicts on a Google-signed Gemini JPEG: the 1,037,497-byte original is Trusted, a libjpeg-turbo jpegtran -copy all -optimize copy with the same pixels is Invalid (dataHash.mismatch), a cjpegli quality 90 copy has no claim.

Does compression remove Content Credentials? Two signed Gemini images through 13 tools

We took an image made by Nano Banana 2, one of Google's Gemini image models, and asked c2patool whether its Content Credentials hold. It answered "Trusted": a C2PA manifest signed by Google LLC, stating "Created by Google Generative AI.", with every hash matching. Then we ran that JPEG, and a PNG from the original Nano Banana, through 13 tools, WordPress 7.1.2 and Iminify among them, and asked again. Every file those tools wrote failed if it differed from its source by even a byte. Most tools dropped the manifest. Five kept a copy of it that no longer verified, in some cases without changing a single pixel. If a compressed file has to carry a working credential, something has to sign it again after the last byte changes, and that adds bytes of its own.

Oct 14, 2026 8 min read

Bar chart of the resized files WordPress 7.1.2 made on the server and in Chrome: 691 and 640 KB for a 1800 px photo, 1,942 and 2,193 KB for its 6000 px version, 553 and 651 KB for a PNG screenshot.

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Does WordPress compress images? What WordPress 7.1 does to your upload

We uploaded the same photo to a fresh WordPress 7.1.2 site twice, both times from Chrome. The file we sent, 832 KB, was stored byte for byte both times. From it WordPress made five resized copies at JPEG quality 82. Through Media > Add Media File those copies came to 691 KB. Through the Upload button on an Image block they came to 640 KB, because in 7.1 that button has the browser make the copies instead of the server. So does WordPress compress images automatically? Not the file you upload, which is stored byte for byte. It re-encodes the resized copies it makes, the JPEG ones at quality 82. In our test a phone and a standard laptop screen downloaded copies of this photo, but a 2x laptop screen got the untouched original, so compressing it is still your job. Since 7.1, which program makes the copies depends on the button you press and the browser you press it in.

Oct 5, 2026 8 min read

ComfyUI's Flux Dev example render of a fox-eared girl in a maid dress holding a cake, captioned: 1,215,064-byte PNG to 125,684-byte WebP, and the workflow still loads in ComfyUI.

ComfyUI PNG to JPG loses the workflow. WebP and AVIF can keep it

ComfyUI's Flux Dev example image is a PNG of 1,215,064 bytes, and the two text chunks holding its prompt and workflow take 12,240 of them. The rest is 1024x1024 pixels stored without loss. Across the 92 PNGs in ComfyUI's examples repository that carry a workflow, the text was no more than 3.32 percent of any file, with a median of 0.62 percent. Converting to JPG shrinks the file, but ComfyUI's own loader can't read a workflow back out of a JPG. A WebP or AVIF can keep it, at about a tenth of the size. We took the text-to-image examples of ten models from ComfyUI's examples repository, made smaller copies several ways, and dropped the copies back onto ComfyUI 0.37.0's canvas to see which ones still held the workflow.

Oct 3, 2026 6 min read

The fjord photograph from our test set above two bars: 3.07 MB as a PNG and 555 KB as a JPEG at quality 90.

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Why is my PNG file so large? Four causes, measured

We took the fjord photograph from our test images, a 1,800 by 1,200 JPEG of 832 KB, and saved the same pixels as a PNG. It came to 3.34 MB at the default setting of Pillow, the Python imaging library. Through zopflipng, a slower lossless compressor, 3.07 MB. As a JPEG at quality 90 it's 555 KB, and it scores 84.22 on a perceptual scale where 80 means an average observer can't see the difference side by side. A photograph was the most expensive of the four causes in the comparisons below. The four: It's a photograph. It has more pixels than it will be shown at. It stores more per pixel than the picture needs: 16 bits per colour channel, or millions of colours where 256 would do. The program that saved it didn't compress it very hard. Each has its own fix, and the fix for one can be wrong for another. A JPEG rescues a photograph. Our desktop screenshot came out bigger as a JPEG than as a PNG through zopflipng.

Sep 28, 2026 7 min read

Try it on your own images