Before you upload a photo to an online form, you need to know two things: how heavy the file is (its size in KB) and how big the picture is (its size in pixels). If you check both first, you can fix the photo before the form rejects it. This guide shows how to check them on Android, iPhone, Windows and Mac.
KB, MB and pixels: a quick reminder
- KB (kilobyte) and MB (megabyte) measure the file size. 1 MB is 1024 KB, so a photo of 2 MB is about 2048 KB.
- Pixels measure the picture size, for example 200 x 230 means 200 pixels wide and 230 pixels tall.
Forms often ask for both. A photo can have the right pixel size and still be too heavy in KB, or the other way round.
Check the size on an Android phone
- Open the Files app (or My Files on some phones) and find the photo.
- Long-press the photo to select it.
- Tap the three dots or the Details / Info option.
- You will see the file size, and often the resolution (pixels) too.
You can also open the photo in the Gallery or Google Photos app and swipe up, or tap the info (i) icon, to see the file name, size and dimensions. The exact menu depends on your phone brand and version, but the info option is always similar.
Check the size on an iPhone
- Open the Files app and find the photo (or save it there first from the Photos app).
- Touch and hold the photo.
- Tap Get Info.
- Read the Size, and the Dimensions if it is shown.
In the Photos app, open the picture and tap the info (i) button or swipe up. On newer versions of iOS, this panel also shows the file type and size.
Check the size on a Windows computer
File size: right-click the photo, choose Properties, and look at Size on the General tab. Read the number next to “Size”, not “Size on disk”, because “Size on disk” can be larger.
Pixel size: in the same Properties window, open the Details tab and look under the Image section for Width and Height in pixels.
Check the size on a Mac
Select the photo in Finder and press Command + I (or right-click and choose Get Info). The Size is shown at the top. Open the More Info section to see the Dimensions in pixels.
The easy way: use our tool
Open our Photo Resizer and choose your photo. As soon as it loads, the tool shows the original size in pixels and KB below the picture. You can then set the size you need and let the tool bring it under your KB limit in one step. Your photo is not uploaded anywhere, because everything happens in your browser.
How to read the numbers
- Size shows MB (for example 2.4 MB): multiply by 1024. That is about 2458 KB, which is much larger than a typical form limit like 50 or 100 KB.
- Size shows KB: compare directly with your form’s limit.
- Small “kb” and capital “KB”: forms usually mean the same thing, but check the instructions. Strictly, a small “kb” means kilobits, which is not the same as kilobytes. In everyday form instructions, both almost always mean file size in kilobytes.
What to do after checking
- Size above the limit: reduce the pixel size and the quality. See our guide on how to reduce photo size to 50 KB.
- Size below the minimum: use a larger pixel size or a better original photo.
- Pixels different from the form: resize to the exact width and height, and keep the shape natural by cropping rather than stretching.
- Everything matches: open the final file once and check that your face is clear before you upload it.
Frequently asked questions
Why is the size on my phone different from what the form shows?
Some phones round the number. A file shown as 50 KB may be slightly above or below 50 KB. If the form is strict, keep your photo a few KB below the limit.
Does renaming a file change its size?
No. Renaming changes only the name and the extension label, not the actual file.
Does a screenshot of my photo reduce the size?
It may change the size, but it also lowers the quality, and the screenshot has the pixel size of your screen. It is better to resize the original photo properly.
Can I check the size on the form website itself?
Most forms show an error only after you upload. Checking first on your device saves time.
Sarkari Photo Tools is an independent website and is not connected to any government department. Please always check the official instructions of your form.