Outpaint

You take a vertical photo. You want a desktop wallpaper. You crop, you stretch, you give up. Every existing tool either ruins the original image or charges enterprise pricing for an obvious consumer need.

Outpaint uses mask-based AI outpainting, powered by Replicate's FLUX Fill Pro model, to extend the background of any image into a new aspect ratio. The original pixels are preserved exactly. The new pixels are generated to blend seamlessly. You pick the target resolution (or a preset: Desktop 16:9, Instagram Story 9:16, 4K, custom), choose where the original anchors, and the model fills in the rest.

A scene-complexity check (GPT-4o Vision, with a Laplacian edge-density fallback) tunes the model's guidance and step count per image, and a people-detection pass helps avoid the kind of disconnected "collage" artifacts that plain outpainting is prone to on busier photos.

It's a low-friction consumer tool with one price: £1.50 per finished image, no account, no editor lock-in, no subscription. Generating and regenerating are free, so a customer never pays for a result they don't like.

Outpaint is live at outpaint.co.uk and has taken real payments through Stripe. Since the initial launch it's had a full front-end rebrand — a new logo and a light theme with the logo's own blue-to-orange gradient replacing the original dark/purple design — plus a round of usability fixes: a warning (rather than a silent stretch) when someone picks a target resolution that matches their upload, and clearer validation on the age/terms checkbox before checkout.

The paywall now lives on the server. It began as a CSS blur over the finished image, which anyone with developer tools could have bypassed. The full-resolution result is now held in private storage and streamed only after the server re-checks the payment with Stripe, so a leaked link can't outlive its result, and a failed AI generation is never sold. A Stripe webhook ledger records every payment, refund and dispute, and GDPR erasure anonymises payment rows rather than deleting them, to keep the tax-retention trail.

A production collage bug, root-caused rather than patched. Some results came back looking like two separate pictures butted together. The cause was the tuning logic raising guidance for detailed scenes, which pushed the model to paint its own description instead of continuing the photo. It's now inverted into a narrow band, with complexity expressed through step count, and every generation records its seed, guidance and expansion ratio, so quality is tuned from data instead of eyeballing outputs. A second cause turned up in the logs: a phone-sized 9:16 target invents about 58% of the image, past the point where a single pass stays coherent.

Findability and trust. The site gained a how-it-works page and four use-case pages (uncrop a photo, change aspect ratio, phone wallpaper, extend an image) with matching structured data, a generated share card, and a real before/after example so a first-time visitor sees output before being asked for £1.50. The homepage tool also now reveals the explainer with a scroll-driven curtain effect built in plain CSS position: sticky.

Outpaint started life as Wallpaper.AI in January 2026: a weekend experiment to test whether mask-based outpainting could produce results good enough to actually use. The prototype worked, the use case clearly extended beyond wallpapers, and the project was rebranded and rebuilt as a proper commercial SaaS with usage-based pricing. Sales advisor sessions with Business Wales completed; currently running as a sole trader.