PNG format: lossless images with transparency
PNG is a lossless raster format built for crisp graphics, screenshots, and images that need transparency. It preserves every pixel exactly, at the cost of larger files than lossy formats for photographic content.
Choose PNG whenever edges, text, or a transparent background must stay perfectly sharp. For large photographs where file size matters more than pixel-exact fidelity, a lossy format like JPEG or WebP will usually be smaller.
PNG's lossless compression model
PNG stores images losslessly: decoding a PNG reproduces the original pixels exactly, with no compression artifacts. It achieves smaller files by first applying reversible filters to each row of pixels and then compressing the result with the DEFLATE algorithm.
Because the process is fully reversible, you can open, edit, and re-save a PNG repeatedly without any generational quality loss — a key difference from lossy formats like JPEG.
The format is defined by the W3C PNG specification, which is why PNG is supported natively across browsers and operating systems.
Alpha transparency
PNG supports an optional alpha channel that stores per-pixel transparency, so an image can fade smoothly from opaque to fully transparent. This makes PNG the standard choice for logos and UI elements that must sit cleanly over any background.
PNG uses unassociated (non-premultiplied) alpha, and transparency can also be expressed more compactly for indexed-color and grayscale images through a dedicated transparency chunk when a full alpha channel is not needed.
Why PNG suits screenshots and logos
- Flat colors and hard edges stay perfectly crisp because nothing is discarded.
- Text remains legible at the pixel level, unlike under lossy compression.
- Transparency lets a logo or icon blend with any page background.
- Repeated edits do not accumulate quality loss, which suits works in progress.
PNG color types and bit depths
| Color type | Alpha | Allowed bit depths |
|---|---|---|
| Grayscale | Optional | 1, 2, 4, 8, 16 |
| Indexed-color (palette) | Via palette | 1, 2, 4, 8 |
| Truecolor (RGB) | Optional | 8, 16 |
Choosing a color depth
PNG supports several color types and sample depths from 1 to 16 bits, letting you match the file to the image. An indexed-color palette can dramatically shrink logos and flat graphics that use only a handful of colors, while truecolor RGB with an alpha channel suits richer images that need smooth transparency.
Higher bit depths preserve more tonal precision but produce larger files, so pick the smallest depth that still represents the image faithfully.
Current PixMovo settings
PixMovo can convert PNG, JPEG, and WebP images to and from one another. Selecting PNG as the target produces a lossless file that preserves transparency where the source has it.
Metadata is stripped by default during conversion, and the same conservative format allowlist governs both uploads and targets. PixMovo does not currently export animated PNG (APNG) or non-allowlisted formats from the image tool.
Worked example: exporting a transparent logo as PNG
- Prepare a source with transparency
Start from an image that already has a transparent background, such as a design exported from a graphics editor.
- Convert to PNG in PixMovo
Upload the file and choose PNG as the target format so the alpha channel is preserved.
- Verify the transparency
Place the exported PNG over a colored background. The edges should stay clean with no white box around the logo.
Use an image converter
Frequently asked questions
- Is PNG lossless?
- Yes. PNG reproduces the original pixels exactly, so there are no compression artifacts and no quality loss when you re-save.
- Does PNG support transparency?
- Yes. PNG has an optional alpha channel for smooth per-pixel transparency, which is why it is popular for logos and icons.
- Why are my PNG photos larger than JPEG?
- PNG is lossless, so it keeps every detail of a photograph. Lossy formats like JPEG or WebP discard detail to reach smaller sizes.
- When should I use PNG instead of JPEG?
- Use PNG for screenshots, logos, line art, and anything needing transparency or perfectly sharp edges. Use JPEG for large photographs.
- Does PixMovo keep transparency when I convert to PNG?
- Yes. Converting to PNG preserves the alpha channel where the source image has transparency.