PNG and GIF are not interchangeable
Both are “lossless” in marketing copy. They are not the same. PNG losslessly stores 24-bit color and 8-bit alpha. GIF losslessly stores a palette of up to 256 indexed colors and a single transparent index. When you convert PNG to GIF you are quantizing. A logo with three flat colors will look identical. A PNG photograph or a UI screenshot with gradients will band. Soft drop shadows become a crunchy halo because GIF cannot do 30% opacity; a pixel is either there or not.
That 1-bit transparency is the surprise that bites designers. A PNG logo with anti-aliased edges against transparency has gray fringe pixels. GIF will either make those fringe pixels opaque (wrong matte) or punch them out (jagged). If you must ship GIF, flatten the logo onto the real background color in PNG first, then convert, or accept a hard edge.
When the conversion is reasonable
Pixel art, 8-bit style illustrations, simple icons, and comics with a limited ink set are GIF-native. The palette is a feature. File size can be excellent. Photographs, product cutouts with hair, and anything with a glow are GIF-hostile. For those, keep PNG or use WebP/AVIF. If the only problem is file size on a PNG photo, compress the PNG or convert to JPEG/WebP; do not GIF it.
Animation is not created here. A still PNG becomes a still GIF. People who want a looping sticker need a timeline, not a format hop.
Size, dither, and browser encoding
Dithering mixes palette colors to fake a gradient. It can hide banding and it can add noise that inflates the GIF. For icons, turn dither mentally “off” by starting from flat colors. For photos (if you insist), dither may look less posterized but the file may rival the PNG.
ToolPin runs in the tab. The PNG is not sent to toolpin.online. Limit 250 MB—again, you should convert small graphics, not 4K marketing PNGs, to GIF. No watermark, no account. Indexed PNGs may already be 256 colors; the GIF can be a near copy. 16-bit or huge PNGs are reduced through the canvas first.
Prefer PNG unless you are forced
Modern web, iOS, Android, and almost every CMS accept PNG. GIF’s remaining niches are nostalgia, very old mail software, and a few game or forum stacks. If you control the page, ship PNG or WebP. If a spec says GIF, convert, then keep the PNG as the master because you cannot get the lost alpha or colors back from the GIF.