What a GIF file actually holds
GIF is one of the oldest image formats still in daily use. It dates from 1987, stores at most 256 colours per frame from a fixed palette, compresses those palette indexes losslessly with LZW, and supports a very basic kind of transparency: each pixel is either fully see-through or fully opaque, with nothing in between. On top of that single-frame model it can chain several frames with delays, which is why the word GIF now mostly means a short looping animation from a chat app or a reaction image.
Files like this come from messaging apps, sticker packs, screen recorders that export GIF, old clip art collections and legacy web graphics. Many upload forms, CMS media libraries and design tools either refuse GIF outright or handle it badly, which is usually the reason someone needs a PNG instead.
Animation is dropped: you get the first frame
This converter decodes the GIF with the browser's own image decoder (createImageBitmap) inside a Web Worker. That call returns a single still bitmap, and for an animated GIF that bitmap is the first frame. The tool does not step through later frames, does not let you pick a frame and does not composite frames together. If frame one is a blank or a title card, that is what you will get.
When you need a specific moment from an animation, pause it in a player and take a screenshot, or extract frames with a video editor first. For a GIF that was already a still image, none of this matters and the conversion is exact.
What changes on the way to PNG
PNG is lossless, so nothing is thrown away from the pixels that survive. There is no quality slider on this page because the PNG encoder in the worker has no lossy mode. The output is a 32-bit RGBA PNG: 8 bits each for red, green, blue and alpha. The GIF's hard 1-bit transparency maps cleanly onto that alpha channel, so transparent areas stay transparent, but the converter does not invent soft, anti-aliased edges. Jagged outlines in the GIF remain jagged in the PNG.
Colour is the other thing to keep in mind. The GIF only ever contained up to 256 colours, and converting to a true-colour format does not add any back. A dithered GIF photo will still look dithered as a PNG. Any comment blocks or application extensions inside the GIF are discarded, and the PNG carries no metadata at all.
File size: a worked example
Because the tool always writes a full RGBA PNG rather than a palette PNG, small stills can actually grow. A 480x270 single-frame meme of about 90 KB typically becomes a PNG of 120 to 200 KB. Flat graphics with large areas of one colour compress well under PNG's deflate stage, so a 600x400 logo GIF of 30 KB often lands around 25 to 40 KB either way. Going the other direction, a 2 MB animated GIF with sixty frames turns into one frame of perhaps 100 to 200 KB, simply because 59 frames are gone. These are typical figures, not promises, and the exact result depends entirely on the picture.
If the PNG is larger than you hoped, run it through the image compressor, or convert to a lossy format with GIF to WebP instead.
When to convert and when to leave it alone
Convert when a form rejects GIF, when you want a clean thumbnail of an animation, or when you plan to edit the image in an app that treats GIF poorly. Keep the GIF when the animation is the whole point, or when a tiny palette GIF is already smaller than any PNG could be. Multiple files can be dropped at once; they are converted one after another and each PNG is downloaded separately, always on your own device. For more on where PNG fits among the other formats, see PNG vs JPG.