Check Image File Size
Before you hit an upload limit, check exactly how big your image is. You get the size in bytes, kilobytes and megabytes, plus how efficiently the image is compressed.
- Never uploaded
- Instant, no sign-up
- Works offline
About this tool
If it's too big for a form, email or chat app, one click takes you to the compressor, or to the exact-size pages for common limits like 50 KB and 100 KB.
How it works
- 1
Add an image (or try the sample).
- 2
The report appears instantly.
- 3
Copy the values you need — nothing is uploaded or changed.
Features
- Every unitBytes, KB and MB, calculated precisely (1 KB = 1024 bytes).
- Compression insightBits per pixel and the ratio compared with raw pixels.
- Next stepA direct link to shrink the file if needed.
- Private by designEverything runs on your device. No uploads, no account, no watermark, and EXIF/GPS data is stripped from the result.
Supported formats
Input: JPG, PNG, WebP, GIF, BMP, SVG, AVIF, plus TIFF/HEIC where your browser can decode them. Nothing is changed or downloaded — it's a read-only check.
Frequently asked questions
Is 1 MB 1000 KB or 1024 KB?
This tool uses 1024, as most operating systems do. Some websites use 1000, so leave a little margin under a limit.
What is bits per pixel?
The file size in bits divided by the pixel count. Lower means stronger compression.
How do I reduce the size?
Use the compressor, or the Compress to 20/50/100 KB pages for exact limits.
Are my images uploaded to a server?
No. Files are decoded, processed and re-encoded by your browser using the canvas API and Web Workers. Nothing is sent to any server, and there is no account or storage. Closing the tab discards everything.
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