No. Send a PNG, TIFF or high-quality JPEG instead, or better still a vector file. The usual explanation, that WebP is low resolution, is not quite right: WebP can hold very large lossless images. The real problems are that it carries no reliable print-resolution metadata, that its lossy mode hides artefacts which only appear at print size, and that most print software and print-on-demand uploaders will not accept the format at all.
In this article
What WebP is actually for
WebP was built by Google to make web pages load faster. At the same visual quality it is usually a good deal smaller than a JPEG or PNG, it supports transparency, and it supports animation. For its intended job it is an excellent format, and most of the images on most modern websites are WebP for good reason.
That is also the whole problem. Every design decision in the format optimises for a screen: a fixed pixel grid, a known viewing distance, an 8-bit RGB colour space, and a file that will never be scaled up. Print inverts almost all of those assumptions.
So the question is not whether WebP is a good format. It is whether a format tuned for screens carries the information a printer needs. It does not.
The four real reasons it fails for print
It has no native field for print resolution. This is the strongest technical objection and the one that is almost never mentioned. PNG stores physical dimensions in a dedicated chunk. JPEG stores density in its header. TIFF has explicit horizontal and vertical resolution tags. WebP has no equivalent of its own; resolution can only ride along inside optional EXIF or XMP metadata that most encoders never write and most software never reads. Hand a print operator a WebP and nothing in the file says how large it is meant to be printed.
Its lossy mode hides its own damage. Lossy WebP is very good at discarding detail your eye will not miss on a phone. Blown up to the back of a hoodie, the same discarded detail becomes visible as soft edges, faint blocking around high-contrast lines, and mushy gradients. The artefacts were always there. Print simply enlarges them past the point where the compression's assumptions hold.
Most print software will not open it. Print-on-demand uploaders, RIP software and factory artwork pipelines overwhelmingly expect PNG, TIFF, JPEG, PDF, AI or SVG. A file that has to be converted before anyone can look at it is a file that will be converted by someone who does not know what it is meant to look like.
It cannot carry the things print needs. No layers, no paths, no spot colour definitions, no CMYK, no vector data. If a design needs a named colour matched exactly, or a cut line, or a separation per screen, WebP has nowhere to put any of it.
What 300 dpi actually means
Almost every guide tells you to use 300 dpi, and almost none explain that dpi is not a property of an image on its own. It is a ratio between pixels and physical size. The same file is 300 dpi at one size and 72 dpi at another.
What actually matters is pixel dimensions at the final printed size. Work backwards from the garment:
| Print area | Physical size | Pixels needed at 300 dpi |
|---|---|---|
| Left chest | Roughly 9 cm wide | About 1,060 px wide |
| Standard front print | Roughly 28 cm wide | About 3,300 px wide |
| Full back print | Roughly 35 cm wide | About 4,130 px wide |
| All-over panel | Roughly 60 cm wide | About 7,090 px wide |
Two things follow. A 1,200 px logo saved from a website is fine on a chest and hopeless across a back, and no amount of changing the dpi setting will alter that, because changing dpi without resampling only relabels the file. Upscaling in software invents pixels that were never photographed or drawn, and on a garment that reads as softness.
Sublimation and all-over printing are the least forgiving, because the panels are large and the colour goes into the fibre rather than sitting on it. There is no ink layer to hide a soft edge behind. Our guide to what a sublimation printer is covers why that is.
What to send instead
| Format | Best for | Watch out for |
|---|---|---|
| AI, EPS, SVG or PDF (vector) | Logos, type, flat graphics, anything with hard edges | Fonts must be outlined or supplied |
| TIFF | Photographic artwork at final size | Large files, so send a link rather than an email attachment |
| PNG | Raster artwork needing transparency | Lossless, so it will not fix damage already baked in |
| PSD | Layered work where elements may need moving | Include the linked assets or embed them |
| JPEG at maximum quality | Photographs where nothing else is available | Never re-save repeatedly, each save loses more |
Vector is the answer whenever the design allows it. A vector file has no resolution, so it is correct at every size from a woven label to a back print, and it can be separated for screen printing or scaled for a panel without any loss at all.
Converting a WebP without making it worse
Converting recovers nothing. If the WebP was saved lossily, the detail is already gone and every format you convert to will faithfully preserve the damage. Convert anyway, because you need a file people can open, but treat it as a last resort rather than a fix.
- Find the original first. Ask the designer for the source file. Five minutes of asking beats any amount of conversion.
- Convert to PNG, not JPEG. PNG is lossless, so it will not add a second generation of compression damage on top of the first.
- Set the physical size deliberately. In an image editor, set the document size to the actual print dimensions and check what resolution that leaves you with. If the answer is well under 300 dpi, you have found a real problem rather than a settings problem.
- Do not upscale to hit a number. Resampling up to reach 300 dpi produces a file that satisfies a checkbox and prints exactly as softly as the smaller one did.
- Look at it at 100 per cent. Zoom to full size on screen and inspect the edges. What you see there is roughly what the garment will show.
If step four tells you the artwork is too small, redraw rather than stretch. For a logo that usually means rebuilding it as vector, which is worth doing once and then never again.
A factory needs something different from a POD platform
Most advice on this question is written for print-on-demand, where you upload a file to a platform, it goes onto a bought-in blank, and a customer receives one unit. The file requirements are strict because nobody is going to look at your artwork before it prints.
Cut-and-sew manufacturing works differently. Garments are made from cloth rather than bought finished, artwork is laid onto flat pattern pieces before anything is sewn, and a person looks at your files. That changes what is useful to send.
A platform wants one flattened file at exact dimensions. A factory would rather have the layered original, the vector logo, the colour references, and a note about where the design should sit and how it should cross a seam. Detail that a platform would strip out is exactly the detail that lets a factory make a considered decision.
It also means a wrong file is a conversation rather than a failed order. If what you send will not print well, we tell you before anything is cut.
The file checklist
- Vector wherever the design allows it, with fonts outlined
- Raster artwork sized to the real print area, not to a screen
- Colour references written down for anything that must match exactly
- Transparency where the background should not print, rather than a white box
- The original layered file alongside the flattened one
- A sentence saying how large the design should be on the garment
The last one is the most commonly missed and the cheapest to supply. Files arrive every week with no indication of intended size, and the file itself, particularly a WebP, cannot answer the question.
Working with us
We are a cut-and-sew manufacturer rather than a print-on-demand service, so we make the garment as well as decorate it. That means artwork gets checked by a person before production, and it means we can tell you when a design would work better as embroidery, or when a colour will not hold on the fabric you have chosen.
You do not need a tech pack and you do not need print-ready files to start. A reference image and a description is a normal beginning, and we build the technical side from there. Runs start at 50 pieces per style, explained in our guide to minimum order quantity, and sampling is not charged separately when you commit to a bulk run with a deposit.
If you are still choosing a factory, our guide to finding a clothing manufacturer in the UK covers what to ask before you pay anyone. Otherwise, send us the artwork on WhatsApp and we will tell you whether it will print.
Questions
Can I use a WebP image for print on demand?
No. Most print-on-demand platforms reject the format outright, and the ones that accept it convert it themselves with no knowledge of the intended print size. Convert to PNG or TIFF first, or supply vector, so that you control the result rather than a stranger's default settings.
Is WebP genuinely lower quality than PNG?
Not necessarily. Lossless WebP is mathematically identical to the source, the same as PNG. The problem is that most WebP files in circulation are lossy, because that is what the format is used for, and lossy compression that is invisible on screen becomes visible at garment size.
Will converting WebP to PNG improve the print quality?
It makes the file usable, not better. Compression damage already in the WebP is preserved exactly by the conversion. Converting is worth doing so the file can be opened and placed, but if the original was soft or small, the PNG will be soft or small too.
What resolution do I actually need?
Around 300 dpi at the finished printed size, which is a pixel count rather than a setting. A 28 cm front print needs roughly 3,300 pixels across. Changing the dpi number in an image editor without resampling changes nothing about the image.
Should artwork be RGB or CMYK?
It depends on the decoration method, so ask rather than guess. Digital methods such as sublimation and direct-to-garment work from RGB. Screen printing works from separations and named colour references, where a code matters far more than the colour space. Sending the wrong one is rarely fatal; sending no colour reference at all is the real problem.
My designer only sent me a WebP. What now?
Ask for the source file, which will usually be an Illustrator, Photoshop or Figma document. A WebP is almost always an export for a website rather than the thing the design was made in, so the original nearly always exists and is nearly always better.
Related reading
- What is a sublimation printer? — why large panels are the least forgiving of soft artwork
- Streetwear fabric guide — which cloth suits which decoration method
- Minimum order quantity, explained — why runs start at 50 pieces
- How to find a clothing manufacturer in the UK — what to ask before you commit
- How to make a tech pack, and what to do if you cannot – what goes in one, and why you do not need one to start
- What is sublimation printing, and what is it good for? – the process, why cotton fails, and how it compares with DTF
- How to screen print t-shirts, at home and in production – the process in full, and where doing it yourself stops working
