Image dimensions checker for pixel width and height

Measure the saved image you will upload

Select the actual exported file rather than looking at its thumbnail or the size of an editor window. A preview can be scaled to fit the screen. That tells you how it is displayed, not necessarily how many pixels the stored image contains.

If you have several copies, check the one that will go into the destination's form. A messaging app, a screenshot or a previous resize can create a smaller version. The original camera image's dimensions do not describe every copy made from it.

This checker accepts one image at a time within the 25 MiB per-file limit. It supports recognised JPG, PNG, WebP, GIF and HEIC inputs with format-specific limitations. A PDF is not an image input here; use the PDF page size checker for a document's page geometry.

What the reported width and height mean

The detailed inspector reads dimension information from supported image structures. The displayed width and height are a measurement of that image data, not an assessment of its clarity. A header can provide dimensions even though the picture still needs to be opened and reviewed for visual problems.

Width comes before height. An image described as 1200 × 800 has a wider pixel grid than it is tall; swapping the values changes the shape. Two images can contain the same total number of pixels and still have different widths and heights.

Recognised HEIC files are a special limitation: their pixel dimensions remain unavailable in this check until a compatible decoder reads them through an appropriate conversion workflow. Do not treat missing dimensions as zero or as confirmation that a requirement has passed.

Enter exact sizes or ranges correctly

If the receiving form requires an exact width, put that number in both minimum and maximum width. Do the same for an exact height. A minimum alone only tests that the image is not too small, while a maximum alone only tests that it is not too large.

An instruction such as at least 800 pixels wide does not imply exactly 800. Similarly, a maximum height does not establish a minimum height. Copy the actual conditions without adding constraints the receiving service never gave.

For a fictional requirement of 400 × 600 pixels, a 600 × 400 image fails despite using the same numbers. For a range, compare each axis separately. These examples explain the fields; they are not specifications for passports, social platforms or any other named service.

There is no dedicated aspect-ratio rule field in this interface. Where a destination specifies a ratio rather than exact dimensions, compare width and height yourself as well as checking any numerical limits. Do not assume the absence of a ratio warning means it was tested.

Keep a copy of the destination's instructions beside the report. That makes it easier to spot a transposed number before you spend time editing a correct image.

Orientation can complicate the comparison

Some photographs store orientation information separately from the pixel grid. Different applications can present that information differently. If the numbers or preview seem sideways, open the original in a trusted viewer and establish the intended orientation before changing anything.

The separate orientation tool can normalise supported images using decoded pixels. After any change, inspect the exported copy's dimensions again. A portrait and landscape interpretation can swap the roles of width and height, which matters for an exact upload requirement.

Do not rotate or stretch an official photograph simply to make two numbers agree. The subject's appearance and the receiving service's composition rules still matter. Numerical compliance is only one part of a suitable submission.

Dimensions, file size and resolution are separate

Pixels describe the image grid; bytes describe its encoded storage. Two pictures with identical dimensions can have very different file sizes because their content and encoding differ. Reducing JPEG quality can lower bytes without changing width or height.

A print measurement in millimetres needs an intended resolution before it can be converted into a definite pixel size. If the instructions only give a physical photograph size, look for a separate digital-upload specification or ask the organisation. Do not enter millimetres into these pixel fields.

The checker does not certify DPI metadata, printer output or image sharpness. Increasing a stored resolution label cannot restore missing detail. If the source is blurred or a small thumbnail, a better original may be necessary even when its numerical dimensions are enlarged.

Use the result to choose an appropriate edit

If the image is larger than required, a proportionate resize may be useful where the destination allows it. If the shape is wrong, cropping or permitted padding may be needed in a suitable editor. Those operations have different effects and should not be confused.

Cropping removes content. For a photographed document, make sure names, dates, signatures, stamps and page edges remain visible where required. For artwork, ensure the important subject is not cut off. Resizing the entire picture may be preferable when its shape already matches.

Enlarging creates more pixels but cannot guarantee additional real detail. Do not judge the outcome only by a passing width and height check. Review faces, text and fine edges at the size the recipient is likely to inspect.

Understand incomplete or failed results

If the file structure cannot be verified or the dimensions are unavailable, obtain the original again or try an appropriate supported export. An unfamiliar or incomplete file should not be assigned invented dimensions. The checker reports its scope rather than claiming to read every image variant.

An issues-found result can also concern another rule you entered, such as file size or allowed format. Read the individual findings. A dimension pass does not cancel an unrelated format failure, and a small file is not automatically the correct shape.

Once you have a suitable output, check that saved file again and keep the original. If the destination still rejects a picture that matches the stated numbers, investigate its remaining requirements or ask support. Repeated resizing without a reason can make a good image worse.

Questions that come up