Flatton is an online flatting tool for illustration and comic line art. Users upload a PNG line drawing, click “Flatten Art,” and the system fills enclosed white areas with random light or mid-tone color blocks, expanding those blocks underneath the line art. The result is a base-color separation layer that can be placed below the line art layer. It is not a final coloring tool; rather, it prepares the artwork for replacing colors later with the paint bucket or magic wand in software such as Photoshop, Krita, or Clip Studio Paint.
The workflow is very straightforward: upload a PNG, generate flats, save the file, and place it underneath the line art. The site notes that closed lines work best, and Flatton can automatically close small gaps of up to 4 pixels. For cross-hatched areas, users can also use white lines beforehand to open up regions they want grouped into the same color area. Currently, only PNG is supported. Input files must be no larger than 20MB, with a total pixel count under 80 million—roughly enough for A3 at 600dpi. The output may sometimes be an indexed PNG, so users may need to convert it to RGB. Because the generated colors can be very similar to one another, the recommended tolerance for magic wand or bucket fill operations is 0.
The page clearly states that the tool is free to use, and we did not find any subscription, usage-based pricing, or commercial licensing fees. On privacy, the author says images may be logged for diagnostic purposes and are deleted after diagnosis where possible. Apart from that, images are generally not stored on the server; processing is completed in memory and then returned to the browser. If you do not trust the server, there is also a free open-source offline version that can be run locally and inspected in code form, which is a safer option for unpublished work.
Its strengths are simplicity, free access, and a precise focus on the flatting workflow. It can significantly reduce the repetitive work of manually laying down base colors area by area, and the site provides practical workflow tips. Its limitations are a narrow feature set, PNG-only support, and no team collaboration, batch processing, account management, or customer support information. Complex line art may still require preprocessing, and the generated results need further editing in professional art software. Flatton is best suited as a preprocessing utility for comic artists, illustrators, and digital colorists.
The collected text does not provide information on access from mainland China, network stability, or payments. Since the tool is free and no payment details are listed, payment friction does not appear to be a major issue for now. If access is unstable, users can consider downloading the open-source offline version, or use built-in selection and fill tools in Clip Studio Paint, Photoshop, Krita, and similar software as alternatives.
⚠ This review is compiled from public sources and does not constitute a purchase recommendation. Verify all facts on the vendor's official site. Verify on flatto.nl official site.
flatto.nl is an Netherlands Design & Creative provider. TG4G tracks its product information, an overall rating of 7.0/10, and a China-accessibility score of China direct-connect friendly. Click "Visit Official Site" to reach flatto.nl directly.