Calculator
What the Facebook Cover Maker does
Facebook Cover Maker: outputs exactly 820x312 px, the size Facebook uses for Page cover photos. Everything runs in your browser and the file is never uploaded.
Pick a file and the Facebook Cover Maker generates it right here in the page. Processing is local, so speed depends on your machine rather than someone else’s server load.
Getting the dimensions right before upload avoids a lot of downstream cropping. That is usually what brings writers preparing assets for a post here.
Nothing is transmitted: the file is decoded and re-encoded entirely in the browser.
Field definitions, the method, and a worked example from the default values are all set out further down the page.
What do the Facebook Cover Maker fields mean?
The Facebook Cover Maker uses 3 inputs. None of the boxes start empty. The page loads with a worked set of values you can edit or replace.
| Field | What to enter | Default |
|---|---|---|
| Image file | stays on your device | none |
| Export as | choose from PNG, JPEG or WebP | JPEG |
| Quality % | accepts 10 to 100 | 90 |
How does the Facebook Cover Maker work?
Each output is derived from the inputs above in a single pass; there is no hidden state carried between runs, so the same inputs always give the same generated output.
Validation runs before the calculation, which is why a mistyped value shows an error rather than a plausible-looking result.
What a typical run looks like
You provide: Image file, Export as and Quality %
What happens: the file is read into memory by your browser, processed locally, and offered back as a download. It is never uploaded.
You get back: the finished file to download, with a line in the panel saying what was done.
Because the work is local, speed depends on your device rather than our servers, and large files are limited only by available memory.
Facebook covers sizes
Facebook cover photos are cropped differently on desktop and mobile, so the safe area is considerably smaller than the image itself. Designing to the full canvas will get parts of it cut off.
| Use | Size | Ratio |
|---|---|---|
| Page cover photo | 820 × 312 | 2.63:1 |
| Profile cover photo | 851 × 315 | 2.7:1 |
| Mobile display area | 640 × 360 | 16:9 |
| Shared post image | 1200 × 630 | 1.91:1 |
| Profile picture | 360 × 360 | 1:1 |
Worth knowing
- Desktop shows 820 × 312; mobile shows 640 × 360. The area visible on both is roughly the centre 640 × 312: keep anything important inside it.
- The profile picture overlaps the lower-left of the cover on desktop. Do not put text there.
- Uploading at double the listed size (1640 × 624) gives a sharper result on high-density screens.
- Facebook applies aggressive compression. Uploading a PNG for a photographic cover usually results in a worse JPEG than uploading a good JPEG.
Platforms revise their published specifications from time to time. Where a ratio and a pixel size conflict, match the ratio — every platform downscales an oversized image, but none of them will fix a wrong shape except by cropping it.
How to use it
- Choose your file under Image file, or drag it onto the drop area.
- Pick a value for Export as: the options are PNG, JPEG or WebP.
- Set Quality % (10 to 100).
- Press Create.
- Look at Status in the output panel.
- Use Copy Link if you want the same setup again later, or Print for a paper copy.
What this tool does not do
- Re-encoding a lossy format such as JPEG always loses some detail, even at maximum quality.
- EXIF metadata may be dropped during processing, which is usually desirable but is worth knowing.
- The tool answers exactly the question it is given; it cannot know the context around your numbers.
- Garbage in, garbage out: confirm each figure means what you think it does before trusting the result.
- Because everything runs locally, processing speed depends on your device rather than our servers.
Frequently asked questions
Image file, Export as and Quality %. That is the whole form. Each field is pre-filled with a sensible default, so the form is usable immediately, without filling anything in first.
Quality % accepts 10 to 100. Anything beyond those bounds is flagged rather than approximated.
No. The file is read by your browser and processed inside the page. It is never sent to us, which is also why it keeps working offline once loaded.
Free for any use, personal or commercial.
It follows the standard definition for this operation, so the result matches what a reference implementation would give.