Add image background
Flatten see-through PNGs over a solid colour for print and sharing. Never leaves your device.
- Your files are never uploaded
- Processed on your device
- Works offline
- Free, no sign-up
Drop your images here
Images · up to 10 files, 100 MB each
or paste with Ctrl+VLive preview
Settings
Transparent areas are filled with this shade.
JPG is smallest but cannot keep transparency.
How it works
Add transparent images
Drop in PNGs or WebPs with checkerboard holes you want filled.
Choose colour and format
Pick white for print or brand colours for listings, then PNG or JPG.
Download flattened copies
Preview the filled backdrop, then save ready-to-share files.
Give transparent cutouts a solid floor
Transparent PNGs look perfect in editors but confuse print shops, marketplaces and office apps that expect every pixel to be opaque. This tool composites each see-through pixel over the colour you choose using proper alpha blending, so soft rims melt naturally into the new floor instead of snapping to harsh stair-steps. White suits resumes, invoices and product sheets, while soft grey flatters glassware photography and brand pastels make app-store screenshots feel intentional rather than default checkerboard voids.
Matte choice changes mood more than people expect, because semi-transparent edge pixels pick up hints of whatever sits beneath them. A pure white matte keeps jewellery and text crisp, a warm cream softens skin tones for family prints, and deep charcoal turns neon logos electric for banners. Sample thoughtfully against the destination: marketplaces often force white anyway, social feeds reward colour, and printers reproduce off-whites more faithfully than screen-bright hex values that shift on paper and fabric.
PNG keeps holes, JPG cannot
PNG and WebP store an alpha channel, meaning they remember which pixels are see-through and how strongly each edge fades. JPG was built for photographs without any transparency concept, so when you save a transparent image as JPG the holes must be filled with a solid matte — usually white — and that decision is permanent. Choose PNG when you still need to composite later, choose JPG when you need the smallest file for email or forms and are certain no further layering will happen downstream.
Because flattening bakes the matte into the pixels, keep your transparent originals archived separately before converting batches for specific uses. Preview at full size to catch dark fringes where former semi-pixels meet the new floor, especially around hair and motion blur, and try a slightly tinted matte if white rims glow. The tool never upscales or sharpens, it only blends existing pixels over your colour at full resolution for faithful reproduction.
Flattening done beside you, not above the cloud
Product shots and ID graphics often carry commercial weight, therefore blending occurs strictly inside your browser with no background transmission. Whereas bulk converters push transparent masters to queues where they can be cached, thumbnailed or mined, here the alpha compositing and JPG encoding execute in isolated tab memory, so unreleased packaging, signatures and likenesses stay under your roof from import through download without creating shadow copies on infrastructure you do not control.
There is no sign-up, no line and no countdown: open Add image background when a marketplace rejects a PNG, flatten up to ten files, download the solid versions and close the tab. The browser keeps only the app code for offline reuse, never your catalogue. Revisit the preserved transparent masters anytime to render fresh mattes in seasonal colours without generational quality loss from repeated JPG cycles.
Questions
Are my product images uploaded?
No. Flattening runs locally in your browser. Files are never sent to a server.
Is it free?
Yes. Free to use with no sign-up, no watermark and no daily limits.
Why does JPG have no transparency?
The JPG format has no alpha channel by design. Transparent areas must be filled with a solid colour when saving as JPG, so pick PNG or WebP to keep holes.
Which matte colour should I pick?
White for print, forms and most marketplaces. Use brand colours or soft grey for social posts where a solid floor looks more designed.
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