Image size checker

Find out why a photo might be rejected before you upload it. Check pixel dimensions, exact KB and file format against the requirements on your form.

  • Nothing uploadedFiles never leave your device
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  • FreeFree, no sign-up, no watermark

Check an image before uploading

JPG, PNG, WebP, GIF, BMP, AVIF or HEIC · up to 50 MB · stays on your device

Or drag and drop, or paste with Ctrl + V. Files stay on your device.

See the actual file format, exact bytes and pixel dimensions. Add your form’s limits to find what needs changing.

Your form’s requirements

Enter the limits shown on your form. Leave any field empty to skip it. 1 KB = 1,024 bytes.

How to use the Image Size Checker tool

  1. Choose your image

    Select a JPG, PNG, WebP, GIF, BMP, AVIF or HEIC image up to 50 MB. The file is read on your device.

  2. Enter the form’s limits

    Copy the minimum and maximum KB, pixel width, pixel height and allowed format from the application portal. Leave unused fields blank.

  3. Review each check

    See which properties pass. Follow a suggested resize, compression or conversion tool for any property that needs changing.

  4. Check the finished file again

    Choose the downloaded result to confirm its actual properties before submitting it to the portal.

Why use UploadWell’s Image Size Checker?

Exact file size
See bytes as well as KB, so rounded file-manager values do not hide a file that is just over the limit.
Verified file format
Detect supported formats from the file header rather than trusting a renamed extension.
Your requirements
Compare with the limits from your specific form instead of relying on a generic exam preset.
Private inspection
File contents stay in your browser. There is no upload, account or saved copy on our server.

Image dimensions and file size are different checks

A form can ask for a 200 × 230 pixel JPG between 20 KB and 50 KB. Those are three independent requirements: width and height describe the pixel grid, KB describes the file’s stored size, and JPG describes its format. Passing one does not mean the others pass.

This checker uses 1 KB = 1,024 bytes. A 50 KB limit therefore means 51,200 bytes. Some websites use decimal kilobytes instead; if a portal gives an exact byte limit, follow that number and compare it with the exact-byte result shown here.

For example, a 51,201-byte photo is slightly above this checker’s 50 KB maximum, even if your computer rounds its displayed size to 50 KB. Aim a little below the limit with Compress Image when the portal’s calculation is unclear.

What to do when a requirement fails

ProblemNext step
File is too largeUse Compress Image to reduce the KB size.
Wrong width or heightUse Resize Image to set the required pixel dimensions.
PNG or HEIC where JPG is requiredUse Image Converter to create a real JPG file.
File is below the minimum KBUse the minimum-size option in Resize Image, while retaining the required dimensions.

Renaming photo.png to photo.jpg does not convert it. This checker still identifies the PNG file header. Use the Image Converter to change the underlying file format, then check the new output.

What this checker can and cannot verify

Dimensions reflect the decoded image as displayed, including orientation applied by the browser. A stored DPI tag is shown when it can be read from JPG or PNG; an absent tag is reported as unspecified rather than guessed. HEIC and AVIF decoding depends on browser support and the HEIC fallback.

This tool checks technical file properties. It does not inspect a face, validate a passport background, check a signature’s legibility or guarantee acceptance by a government, school or recruitment portal. Read the current instructions on that portal as well.

No image is modified by this page. Your original stays untouched. After making a change with a linked tool, select the resulting file here again: the checker does not automatically receive files from another page.

Frequently asked questions

How do I check an image’s size in KB?

Choose the image and read File size for KB or Exact size for its byte count. The checker uses 1,024 bytes per KB.

Can I check a photo for an application form?

Yes. Enter the form’s KB range, pixel dimensions and format. The page compares those file properties and links to tools that can change them.

Does changing a filename convert PNG to JPG?

No. The file header stays PNG. Use an image converter to create a genuine JPG.

Why does a 50 KB image fail a 50 KB limit?

The displayed size may be rounded, or the portal may use 1,000 bytes per KB. Compare exact bytes and leave some room below the maximum.

Will passing every check guarantee acceptance?

No. Portals can also check visible content, aspect ratio, faces, background and other rules. This page checks only the requirements you enter.

Are ID photos uploaded anywhere?

No. The browser reads the chosen file locally. Image contents are not sent to UploadWell.

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