Save a drawing in the format that keeps the important details

Let the picture's content guide the choice

Paint.surf offers PNG and JPEG downloads. Choose based on what the picture contains and where it will be used, then inspect the saved result. A familiar extension alone does not guarantee that thin lines or small lettering will look right.

PNG is a useful first choice for line drawings, interface screenshots, flat-color shapes and labels. Its lossless compression does not introduce JPEG-style artifacts around sharp edges, although a detailed photograph may produce a relatively large PNG.

Use JPEG when its tradeoff suits the destination

JPEG can be useful for photographic content when file size matters. Its lossy encoding can soften fine details and add artifacts near high-contrast lettering or outlines. Keep a PNG working copy of a diagram and make a JPEG copy when a destination's format requirement makes that useful.

Repeatedly opening and resaving JPEG copies can add further changes. Start each new export from the best available working image rather than recompressing an already reduced copy. This editor uses its export setting internally; there is no JPEG quality slider in the Save As menu.

Make a comparison from the same canvas

Try the exercise below with a small drawing. Compare both files at the same scale, inspecting the letter edges and the boundary between the black line and white background. Compare their actual file sizes on your device too. There is no fixed rule that one format must always be smaller.

1. Draw a black outlined rectangle on the white canvas.
2. Add a short red label and apply the text.
3. Choose File > Save (PNG). Without changing the canvas, choose File > Save As (JPEG).
4. Open both downloads at 100% and compare sharp edges, label readability and file size.
5. Keep the version that meets the destination's requirements while preserving the details that matter.

Understand what both files leave behind

Both downloads are flattened pictures. They do not preserve editable shapes, text boxes or the editor's undo history. The current document starts on a white background and imported images are drawn over white. Transparent selection is not a promise of transparent-background PNG export.

Rename downloaded copies on your device to keep important stages distinct, such as layout-v1.png and layout-final.png. Before closing the tab, open the latest download and confirm that it contains the work you intended to retain. A file that was saved before the last edit will not acquire that edit automatically.

References

• MDN: PNG, JPEG and other image formats