How do I fill transparent PNG pixels?

Upload a transparent PNG, pick a replacement color (white, black, or any hex), preview the opaque result, and download. Clear and semi-transparent areas are composited over that color.

What is a transparency bucket tool?

A transparency bucket (PNG transparency filler) replaces transparent regions with a solid fill — like pouring a color behind your image. Searchers also look for “fill transparent png pixels” and “transparency bucket tool” for this workflow.

Does it fill semi-transparent / translucent pixels too?

Yes. The fill color is drawn underneath, then your PNG is drawn on top. Fully clear pixels become the fill color; translucent edges blend correctly into an opaque result.

Is this the opposite of Make Image Transparent?

Yes. Make Image Transparent knocks out colors to create transparency. This page fills existing transparency with a solid color to make an opaque PNG.

Why fill transparent pixels before JPG conversion?

JPEG has no alpha channel. Filling transparent PNG pixels with white (or another color) first avoids unexpected black/white flats when converting with PNG to JPG Converter.

Can I choose any fill color?

Yes. Use the color picker or quick presets (white, black, gray). White is the most common fill for logos and screenshots.

Is the tool free? Are files uploaded?

Free, no sign-up. Filling runs entirely in your browser via the Canvas API — images never leave your device.

I want to make the image transparent instead

Use Make Image Transparent to remove a background color, or Change PNG Opacity to make the whole image see-through.

Drop JPEG, PNG, WebP, or GIF here or

Or try an example

Replacement / fill color

Quick fills

Transparent and semi-transparent pixels are composited over this color so the output PNG is fully opaque.

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Fill transparent PNG pixels online

Fill transparent PNG pixels with a solid color online free. Replace clear and see-through areas with white, black, or any hex — a transparency bucket tool that makes opaque PNGs in your browser.

What is a PNG transparency filler?

A PNG transparency filler (transparency bucket tool) replaces transparent and semi-transparent pixels with a solid color so the output is fully opaque. People searching “fill transparent png pixels”, “transparency bucket tool”, and related transparent PNG workflows often need this when a target app, printer, or JPG converter cannot keep an alpha channel. This tool draws your chosen color as a background, composites the PNG on top in the browser, and downloads an opaque PNG. It is the reverse of Make Image Transparent (which creates transparency). For empty transparent canvases see Blank Image; for checking alpha see Check If PNG Is Transparent.

Transparency filler features

Turn transparent PNGs into solid, opaque images.

Solid fill under alpha
Composites your PNG over any hex color so transparent pixels become opaque.
Semi-transparent edges
Soft anti-aliased edges blend into the fill — not hard cutouts.
Quick color presets
One-click white, black, or gray fills for common print and web needs.
Before / after preview
Compare the clear PNG with the filled opaque result.
PNG examples with real alpha
Try sample transparent PNGs before uploading your own.
Private & free
Browser-only transparency bucket — no uploads.

How to fill transparent PNG pixels

Make an opaque PNG in a few steps.

Upload a transparent PNG
Drop a PNG (or other image with alpha) into the tool.
Choose the fill color
Pick white, black, or a custom hex as the replacement color.
Preview
Check that clear regions now show your solid fill.
Download
Save the opaque PNG to your device.

Tips for filling transparent pixels

Get clean opaque results.

01
Default to white for logos
White fill matches most document and email backgrounds.
02
Match brand color for marketing
Use your brand hex so cutouts sit on a consistent solid field.
03
Fill before JPG
Avoid surprise backgrounds when using PNG to JPG Converter after this step.
04
Need transparency instead?
Switch to Make Image Transparent or Remove Background.

Transparency fillers compared

How this free fill-transparent-PNG tool stacks up.

Online PNG Tools (fill transparent PNG pixels)
Competitor ranking for transparency bucket / fill transparent regions. This page matches that intent with color picker, presets, and before/after preview — offline in the browser.
Make Image Transparent (/make-image-transparent)
Creates transparency by knocking out colors. Use Fill Transparent PNG when you already have alpha and need a solid backdrop.
PNG to JPG (/png-to-jpg)
Flattens to white during conversion. Use this filler when you want a custom fill color or to stay in PNG.
This fill tool
Any hex fill, semi-transparent edge blending, free download. Best for fill transparent png pixels workflows.

Great for

When you need opaque output from a transparent PNG.

Prep for JPG / print
Fill alpha before converting or sending to printers that dislike transparency.
Solid logo backgrounds
Place a logo cutout on white or brand color without opening Photoshop.
Screenshots and UI exports
Replace checkerboard transparency with a clean solid backdrop.
Flatten translucent overlays
Bake see-through layers into a single opaque PNG.

Why use this PNG transparency filler

Fast, free, private fill for transparent pixels.

100% free
No account, watermark, or daily limit.
Correct compositing
Fill underneath + draw PNG on top — proper handling of partial alpha.
Privacy first
Everything stays on your device.
Clear intent
Built for fill transparent png pixels and transparency bucket tool searches.

Technical details

How this transparency bucket works.

Method: fillRect with the replacement color, then drawImage of the source (source-over compositing).
Alpha handling: Fully transparent pixels → fill color; partial alpha → blended opaque result.
Output: PNG via canvas export (opaque bitmap after fill).
Processing: 100% client-side Canvas 2D — no uploads.

Sources & References

References on PNG alpha, compositing, and filling transparent regions.

“Alpha compositing is the process of combining an image with a background to create the appearance of partial or full transparency.”
— Wikipedia — Alpha compositing
Alpha compositing: This transparency filler draws a solid color first, then composites the PNG on top — standard “over” compositing that fills clear and see-through pixels. en.wikipedia.org/wiki/Alpha_compositing
“PNG supports an alpha channel for transparency.”
— Wikipedia — PNG
PNG and transparency: Transparent PNGs store alpha per pixel. Filling those pixels with a solid color produces an opaque PNG useful for JPG conversion, print, and apps that do not support alpha. en.wikipedia.org/wiki/PNG
“The Canvas API provides a means for drawing graphics via JavaScript and the HTML canvas element.”
— MDN Web Docs — Canvas API
Canvas API: fillRect + drawImage implements the transparency bucket fill entirely in the browser. developer.mozilla.org/en-US/docs/Web/API/Canvas_API
“The globalCompositeOperation property sets how shapes and images are drawn onto the existing bitmap.”
— MDN — globalCompositeOperation
CanvasRenderingContext2D: globalCompositeOperation: Default source-over compositing is how the PNG is layered on the fill color so translucent edges blend correctly. developer.mozilla.org/en-US/docs/Web/API/CanvasRenderingContext2D/globalCompositeOperation

Frequently Asked Questions

Quick answers about this tool—open a question to read more.