๐๏ธ Letterbox Padding Generator
Drag and drop an image, or click to select
Upload an image, pick a target aspect ratio and bar color, and generate a version padded with solid-color bars (letterbox/pillarbox) to match that ratio โ without cropping or scaling the original image. Handy when a platform requires a specific aspect ratio but you don't want to lose any of the image content.
How to use
- Drag and drop an image, or click to select one.
- Select a target aspect ratio.
- Set the bar color.
- Click "Download PNG" to save it.
How the calculation works
Brings an image to the aspect ratio you choose by adding solid-colour bars above and below or to the sides, without cropping or scaling it. Where the bars go โข Image wider than the target โ bars above and below (letterbox) โข Image taller than the target โ bars on the left and right (pillarbox) The image is always centred, with equal bars on both sides. For printing, there are also 3.5 ร 5 in photo-print (89 ร 127 mm) and A-series paper (A4 and so on, 1 : โ2) ratios, in landscape and portrait.
Worked example
โข A 1080 ร 1080 square to 16:9 โ 1920 ร 1080 (420 pixels each side) โข A 4000 ร 3000 photo to 1:1 โ 4000 ร 4000 (500 pixels above and below) โข A 1920 ร 1080 landscape image to 9:16 โ 1920 ร 3413 (about 1167 pixels above and below) Useful for posting a landscape photo to a vertical video or Story format without cutting anything off.
Things to be aware of
- The bar size is calculated; the original image is never enlarged or shrunk.
- The result is saved as lossless PNG, so photos tend to produce large files.
- Processing happens in your browser; the image is never uploaded.
FAQ
How is this different from cropping?
Cropping cuts off part of the image to match a ratio, but this tool never cuts anything โ it adds padding instead, so the entire original image is preserved.
What's the difference between letterbox and pillarbox?
Letterbox bars are added top and bottom when fitting a wide image into a taller/square ratio; pillarbox bars are added left and right when fitting a tall image into a wider ratio. This tool automatically picks whichever applies based on the image's shape.
Is the image uploaded to a server?
No. All processing happens using your browser's Canvas API โ the image is never sent to a server.