Convert PNG to PDF with Transparency

PDF supports transparency

Modern PDFs (1.4 and later) support alpha channels — pixels can be transparent. When Flint's Image to PDF converts a transparent PNG, the transparency is preserved in the PDF.

What you see depends on the viewer's background colour. Most PDF viewers default to white page background, so transparent pixels appear white. Some viewers (Acrobat with dark mode) may show transparency over a different colour.

Page background colour

The PDF page itself usually has no explicit background — the viewer renders it (typically white). If you want a specific colour behind the transparent PNG, the PDF needs a coloured page background. Flint's PDF editor can add a background fill.

Alternatively, flatten the transparent PNG against your chosen background colour in an image editor before converting. Cleaner result, viewer-independent.

Why transparency might matter

Most documents don't need PDF transparency — they want flat, predictable pages. PDF transparency is useful for: layered designs (logos over photos), composite graphics that need to maintain layer behaviour through editing, or workflows where the PDF will be opened in a design tool that handles transparency.

For everyday document use, flattening is simpler and more universally predictable.

PNG vs JPG for source

If your source image is a photograph, JPG is fine (no transparency anyway). For logos, diagrams, or screenshots with transparent backgrounds, use PNG and let the converter preserve the alpha channel.

FAQ