PNG files cater to transparency and use lossless compression, making them ideal for graphics, logos, and screenshots.
Common Uses
Creating logos and graphics with transparent backgrounds
Saving screenshots and digital artwork
Web graphics requiring transparency
PNG Optimization FAQ
What is a PNG file?
+
PNG (Portable Network Graphics) is a raster graphics file format that caters to lossless data compression and transparency.
Is anything lost when a PNG is converted to another lossless format?
+
No pixel data. PNG stores the image exactly rather than approximating it, so a conversion between two lossless formats is reversible and can be repeated indefinitely without degradation. What can be lost is everything around the pixels — colour profiles, transparency, animation, embedded metadata — because support for those varies far more between formats than the pixel storage does. PNG uses DEFLATE compression over filtered scanlines, so every pixel survives exactly, plus a full 8-bit alpha channel.
Why do screenshots come out as PNG?
+
Because a screenshot is the one image type this format is unambiguously best at. What is on screen is flat colour, text and hard edges — exactly the content lossless compression handles well and a photographic encoder smears — and the operating system knows it, so it does not offer you a choice. Converting a screenshot to a photographic format almost always makes it both larger and worse. PNG is the right choice for screenshots, logos, line art and anything with hard edges or transparency — no ringing, no colour banding.
Why is my PNG so much larger than the same photo as a JPG?
+
Because it is keeping every pixel, and in a photograph almost no two pixels are the same. Lossless compression works by finding repetition, and grain, noise and gradients offer it very little, so the file stays close to its raw size. On a screenshot, a logo or line art the same compression is spectacular. That split — superb on flat colour, wasteful on photographs — is the whole story of when this format is the right one. PNG is a poor photograph format: a photo saved as PNG is routinely five to ten times larger than the same image as JPG or WebP.
Does PNG keep a transparent background?
+
Yes — the format stores a real alpha channel, so cut-out logos, product shots and overlays keep their transparency instead of arriving on a white rectangle. Converting to a format without alpha is where it goes wrong: the transparent areas are filled with a solid colour, usually white or black, and there is no way back short of masking the subject again.
Is PNG the right format for screenshots and line art?
+
Yes, for exactly the reason it is the wrong one for photographs. Interface chrome, text and hard-edged graphics are large areas of identical colour with sharp boundaries, which lossless compression handles efficiently and lossy compression smears — the tell is the faint halo that appears around lettering once a screenshot has been through a photographic encoder. Keep screenshots here and convert only when something downstream insists.
Can I use PNG directly on a web page?
+
Yes — every current browser renders it natively, so it needs no fallback copy and no conversion at publish time. The remaining question is weight rather than support: the same picture in a modern web format is frequently a third of the size at the same visible quality, which is worth doing on anything that appears above the fold.
Who controls the PNG format?
+
Nobody, and that is the point of it. The specification is public, anyone may implement it without asking or paying, and no company can change the terms later — which is why archives, standards bodies and public institutions specify formats like this one for anything that still has to open in twenty years. The trade is not compatibility, which is excellent; it is that there is no vendor to call when some tool implements the spec badly. PNG was designed in 1996 as a patent-free replacement for GIF, and became the web’s default lossless image format.
Can I just rename the extension instead of converting PNG?
+
Almost never, and it is worth understanding why: the extension is a label, while the bytes inside are structured for one specific format. Renaming produces a file whose name promises something its contents do not deliver, and whatever opens it either refuses the file or misreads it. The one narrow exception is two formats that are genuinely the same container under different names — and even then a proper rewrap is safer than a rename.
Can I convert a whole folder of PNG files in one go?
+
With an account, yes — drop them in together and they are queued as one job rather than handled one at a time, with the same settings applied across the batch and the results returned together. Free conversions run a single file at a time (merge tools take two); a paid plan is what unlocks batch processing and the larger per-file limit, which is what makes converting a whole archive practical.
Can I make a PNG bigger without it going blurry?
+
Only modestly. The pixels that were captured are all the detail there is: enlarging either interpolates, which softens edges, or uses an AI upscaler, which invents plausible detail that was never in the original. Both are fine for a step up of a third or so and neither turns a thumbnail into a poster. Start from the largest copy you have and resize down wherever the choice exists.
What happens to my PNG file after the conversion?
+
It is deleted. The upload and the converted result both sit on the server only as long as the job needs them and are then removed automatically; the transfer runs over HTTPS in both directions. Nobody reads the contents, nothing is indexed, and nothing is passed to anyone else. If you would rather not wait for the automatic sweep, closing the job removes the files immediately.
