Forms ask for a photo “under 50 KB” or “between 20 and 100 KB”. A phone or laptop camera makes files of several MB. The built-in photo apps can shrink a picture, but most of them cannot aim for an exact number of KB. Here is what each one can do, and the quick way to hit the limit.
On an iPhone
The Photos app has no setting for file size in KB. Two things help:
- Save photos as JPG. Go to Settings, then Camera, then Formats, and choose Most Compatible. New photos are then JPG instead of HEIC, which most forms accept. For old HEIC photos, use HEIC to JPG.
- Crop the picture to just your face and shoulders. Fewer pixels means a smaller file.
To reach an exact size, open the resize image to KB tool in Safari, choose the photo, enter the limit and download the result.
On Windows
- Open the photo in Paint.
- Click Resize, choose Pixels, and reduce the width (for example to 400 pixels). Keep the aspect ratio ticked.
- Save as JPEG and right-click the file, then Properties, to see its size.
- If it is still too large, reduce the pixels again and save a new copy.
This works, but it takes several tries. The resize image to 50 KB and resize image to 100 KB pages do it in one step.
On a Mac
- Open the photo in Preview.
- Choose Tools, then Adjust Size, and reduce the width in pixels.
- Choose File, then Export, pick JPEG, and move the Quality slider. Preview shows the estimated file size as you move it.
- Save when the estimate is under your limit.
The faster way that works on every device
A browser tool can try different qualities for you and stop at the highest quality that fits. Your photo is processed on your own device, so nothing is uploaded.
- For common limits, use a ready page: 20 KB, 50 KB, 100 KB or 200 KB.
- For exam forms with a set pixel size and a signature, use the photo and signature resizer.
Tips for a photo that gets accepted
- Take the photo in daylight, facing a window, against a plain light wall.
- If the form says “between 20 and 50 KB”, aim for the upper end, so the face stays clear.
- Do not rename a PNG to .jpg. Some portals check the real file type and reject it.
- Keep your original photo, and work on a copy.