Why a website rejects your image upload, and how to fix it

The name on the file is not always the truth. Before changing anything, check the actual format:

• Windows: in File Explorer, turn on View › Show › File name extensions. Then right-click the file, choose Properties, and look at “Type of file”.
• Mac: select the file in Finder and press Command-I. “Kind” shows the format.
• Phone: the file details or info panel in your gallery or files app usually shows the type or extension.

Now compare that with what the form accepts. The help text near the upload button, or the error message itself, usually lists the allowed types.

Many websites now serve images as WebP because the files are small. When you right-click an image in a browser and choose “Save image as”, you often get a .webp file, even if the page looked like it showed a normal photo. Plenty of older forms, desktop programs, and print services still accept only JPG and PNG.

The fix:

• Open Image Convert and drop the WebP file.
• Choose JPG for a photo, or PNG for a logo, screenshot, or anything with a transparent background.
• For JPG, leave quality at 90. That keeps the photo close to the original while producing a reasonable file size.
• Click Convert and download. The file keeps its name with the new extension.

Converting does not change the pixel dimensions. If the form also has a size limit, see cause 4.

iPhones save photos as HEIC by default, and some Android phones offer a similar “high efficiency” option. HEIC files are compact, but many websites do not accept them, and Windows needs an extra extension to open them. Image Compress, Image Convert, and Image Resize do not read HEIC. Convert the photo with HEIC to JPG, or do it on the phone:

• On iPhone, go to Settings › Camera › Formats and choose Most Compatible. New photos will be saved as JPG. Existing photos are not converted.
• For a photo you already took, uploading from the browser on the iPhone itself often works, because the photo picker usually hands the website a JPG copy. If you need a JPG file to keep, save the photo to the Files app, long-press it and look for Quick Actions › Convert Image, or on a Mac open it in Preview and choose File › Export with JPEG as the format.
• On Android, look in the camera app’s settings for an option such as “High efficiency pictures” and turn it off for future photos.

Once you have a JPG, you can resize or compress it with QuickConvert if the form needs that.

Changing photo.webp to photo.jpg in the file name does not change the data inside. Some forms only check the extension and accept it; others inspect the file and reject it; some accept it and then show a broken image later. If you are not sure whether a file was renamed, put it through a real conversion. Image Convert decodes the picture and writes a new file in the format you choose, so the extension and the contents match.

A form that says “maximum 2 MB” will reject a 4.8 MB phone photo even if the format is right. You have two levers: fewer pixels and stronger compression.

• Open Image Compress. Its default long-edge cap of 1920 pixels and quality 80 turn a typical phone photo into a file well under 1 MB, while still looking good on a screen.
• The list after the run shows each file’s size before and after. If it is still too large, lower the cap to 1600 or the quality to 70.

A PNG photo is often the reason for a huge file. PNG is lossless, which is great for screenshots and terrible for camera photos. Converting a photographic PNG to JPG usually cuts its size dramatically.

Some forms check pixel size: “minimum 400 × 400”, “exactly 1200 × 630”, “maximum width 2000 pixels”. Too-small images are usually from screenshots, messaging apps that shrank the photo, or thumbnails saved from a web page. Too-large ones come straight from a camera.

• For a maximum, use Image Resize with Keep aspect ratio on and type the allowed width.
• For an exact shape, crop to that shape in a photo editor first, then resize. The resizer does not crop; with the ratio off, it stretches.
• For a minimum, find a larger original. Scaling a small image up passes the check but looks soft.

This is not a rejection, but it is a common complaint after a “successful” upload. JPG cannot store transparency. When Image Convert turns a transparent PNG into JPG, it fills the transparent area with white, so the result is predictable. If the logo needs to sit on a coloured background, keep it as PNG, or use WebP if the site accepts it.

If the format, size, and dimensions are all within the rules and the form still refuses, consider the other usual suspects:

• Very long file names, or names with unusual characters. Rename to something simple like photo1.jpg.
• A slow or interrupted connection that times out during upload. Try again on a stable network, or with a smaller file.
• Browser extensions that block scripts on the page. Try a private window with extensions disabled.
• The form itself being broken. Contacting the site’s support with the exact error message is sometimes the only fix.

• Format not accepted → Image Convert to JPG or PNG.
• HEIC → HEIC to JPG, or export as JPG on the phone, then continue.
• Too many megabytes → Image Compress.
• Wrong pixel size → crop if needed, then Image Resize.

All three tools run in your browser. The image is processed on your device and is not uploaded to QuickConvert, which matters when the picture is an ID, a signature, or a private photo.

Does converting WebP to JPG lose quality?

Every JPG encode discards a little detail. At quality 90 the difference is very hard to see on a normal photo. Keep the original WebP in case you need it later.

Will converting JPG to PNG make a blurry photo sharper?

No. PNG stores the same pixels without further loss, but it cannot restore detail JPEG already removed. The file usually gets larger.

Can I convert several images at once?

Yes. Drop them all on Image Convert. They all use the format you pick, and they download together as converted-images.zip.

Which formats can QuickConvert read?

JPG, PNG, and WebP, up to 40 MB per file. HEIC, GIF, and PDF are not supported by the image tools.

For more on choosing between formats, read JPG vs PNG vs WebP. To fix a format problem now, open Image Convert.