How to publish a png to 300 dpi in Photoshop

Hi Melissa, This thread is quite old but ill try 🙂

Im "saving as" png, my image which is 300 ppi and it comes out being 72ppi. Im not exporting it, saving as. Am I missing something?

This is an old thread, but as I've stumbled upon it, I'll add my experience and 2 cents. I have to save 300 ppi transparent pngs all the time as I'm a digital graphics creator.

Let me address a couple of things from this thread:

1. Even if you don't need 300 ppi (Dpi) for most printing, most print services ask that you provide 300 ppi. Also, the average customer doesn't understand that pixel dimensions are pixel dimensions no matter what the ppi is. Just give them 300 ppi and save yourself a lot of customer support questions! (A print shop would be savvy about this, but just giving a perspective for say scrapbook designers.
2. Doing an Export to PNG will give you a 72 ppi file - even if the pixel dimensions are the same as the original. You could do as suggested and open it back up and resave to 300 ppi (making sure Resample is unchecked.) This does work, but it will still say 72ppi in the Bridge preview. I didn't notice any upsizing as one person suggested. I usually do a SAVE AS png instead of Export As. Then, I can save to 300ppi. The benefits of Export As though is that it will strip out extraneous metadata which is good if you are giving files to customers who won't understand the pixel dimension / ppi relationship. My way is to export a Photoshop file from Lightroom stripping out the metadata. Then I run actions I've created to make the file transparent and then I run an action to Save As a .png. You could conversely also do an action to save as 300 ppi and batch run that on any files you Export As.

Hope that makes sense!

Save your PNG file, then open it on PS. Change the DPI to 300 and save it again. Just save. Remember you are now editing a png file. No need to export or save as. Just save and be happy  You're done! PNG 300DPI

Photoshop Export/Quick Export strips the resolution metadata, as does Export/Save for Web (Legacy). Photoshop Save As will retain resolution metadata.

The official PNG specification for the PNG resolution unit is in metres (not inches). So a 300 ppi save as PNG from Photoshop would embed a value of 11811 ppm (pixels per metre). When Photoshop opens a PNG with this resolution metadata, it performs a “translation” from pixels per metre to PPI:

118.11 x 2.54 = 299.9994 ppi, rounded up to 300 ppi.

If there is no resolution metadata embedded in the file, then Photoshop defaults to 72 ppi.

Adobe Bridge does not perform the same translation, so there is a discrepancy where Bridge indicates the resolution as 72 ppi when Photoshop indicates 300 ppi. Later versions of Bridge simply show an arbitrary value of 72 ppi if there is no resolution metadata in the file. Earlier versions of Bridge, such as CS6 showed no resolution information at all for PNG files, whether they had resolution metadata or not.

I don't produce t-shirts but I'm pretty sure you don't need resolutions as high as 300dpi as the ink bleeds into the fabric and reduces the resolution. 120-150dpi would be closer to the mark I'd guess, but there are plenty of people here who know exactly how the process works so I'll leave the details to them.