Add Letterbox Bars to an Image
Adapt an image to a cinematic or video format (16:9, 21:9, square...) by automatically adding colored bars at the top/bottom or left/right, without ever cropping the subject.
How It Works
Letterboxing (horizontal bars) and pillarboxing (vertical bars) allow an image to be displayed in a cinematic or video format different from its original aspect ratio without cropping part of the scene. The tool compares your image's aspect ratio with the target format: if the image is relatively wider, bars are added at the top and bottom; if it is narrower, they are added on the left and right.
How does the tool choose between horizontal and vertical bars?
Automatically, by comparing your image's width/height ratio to that of the chosen target format: no manual configuration is needed, and the direction of the bars adapts to each image.
Can I use a color other than black?
Yes, the color of the bars is fully customizable with the color picker: black remains the classic choice for a "cinema" look, but white or a brand color can also work depending on the context.
100% local processing: the bars are drawn directly in your browser via the Canvas API — your image is never sent to a server.