Is JPG image checker
Find out whether a file is truly a JPEG, whatever its extension claims. Everything is checked on your device.
- Your files are never uploaded
- Processed on your device
- Works offline
- Free, no sign-up
Drop your images here
Images · up to 10 files, 100 MB each
or paste with Ctrl+VLive preview
Settings
No settings needed. Add your files and convert.
Nothing is uploadedHow it works
Add your images
Choose one or more image files to check for the JPEG format.
Read the verdict
See the detected format and a clear Yes or No answer for each file.
Act on the result
Convert or rename with confidence, knowing the true format of every file.
Why JPEG identity matters
Many cameras, phones and scanners save photos with slightly wrong extensions, and downloads are often renamed by other apps. A file called photo.jpg might really be a PNG or WebP, which explains upload rejections, odd file sizes and apps that refuse to open it.
This tool reads the file's magic signature rather than trusting its name, so the verdict reflects what the image genuinely is. JPEG and JPG are the same format, so both extensions count as a Yes.
Your files never leave this tab
The check reads only the first few bytes of each file, entirely within your browser on your own computer or phone. Because no image data travels over the network, you can safely inspect personal photos, client work or confidential scans without a second thought.
There is no sign-up, no queue and no expiry: open the checker, drop your files in, read the verdicts and close the tab. The browser cache keeps only the app itself for offline use, never your pictures.
When to check for JPEG and what to do next
Reach for this check when a print shop asks for JPEGs, a form rejects your upload, or thumbnails look wrong after a rename. The report lists the detected format of every file, so mixed-up batches are obvious immediately and you can fix each file correctly.
If a file is not really a JPEG, convert it with our image converter instead of renaming it, so the data matches the extension. For dimensions, file size and colour insight, run Analyze image afterwards.
Questions
Are my files uploaded?
No. The signature check runs inside your browser on your own device. Your files are never sent to us or to anyone else.
Is it free?
Yes. Free to use, with no sign-up, no watermark and no daily limits.
Are JPG and JPEG the same thing?
Yes. JPG is simply the shorter extension for the JPEG format, used when extensions were limited to three letters. This tool answers Yes for both.
What if the format shows as unknown?
The file is probably damaged, incomplete, or in a format browsers cannot recognise. Re-export it from the original app as JPG, PNG or WebP and check again.
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