About this tool
Select files of any type to see their individual sizes and a combined summary. KB and MB are labeled separately from KiB and MiB so you can compare storage use and file size limits accurately.
How to use
- Select one or more files, or drag them into the file area.
- Review each file's byte count, size conversions, extension, and browser-reported type.
- Check the file count, total size, and average size. Select different files or clear the results as needed.
Features
- Works with any file type, including files other than images.
- Shows bytes, KB, MB, GB, KiB, MiB, and GiB with clear unit labels.
- Shows the filename, MIME type, extension, and last modified time in your local time zone.
- Automatically calculates the count, total size, and average size of multiple files.
Size units and timestamps
- 1 KB = 1,000 bytes; 1 MB = 1,000,000 bytes.
- 1 KiB = 1,024 bytes; 1 MiB = 1,048,576 bytes.
- The last modified time comes from the file information provided by your browser. It is not the creation time. Unavailable values are shown as unknown.
- The MIME type supplied by your browser may be blank. It is not a content detection result.
Limits
- Select up to 1,000 files at a time. This tool reads file information without loading the full file contents into memory.
- The files you can select still depend on your browser, operating system, and device. Unlimited file sizes are not guaranteed.
Privacy
All files are processed only in your browser and are never uploaded to a server.
File names, entered text, and results are processed only in your current browser. Your input is not saved automatically. Download any results you want to keep before clearing the tool or leaving the page.
FAQ
What is the difference between KB and KiB?
KB uses a base of 1,000, while KiB uses 1,024. The file contains the same number of bytes, but the converted values differ.
What is the difference between MB and MiB?
1 MB equals 1,000,000 bytes; 1 MiB equals 1,048,576 bytes. These units are not interchangeable.
How large can the files be?
The size checker uses file information without reading the full contents. File selection depends on your browser and device. You can select up to 1,000 files at a time.
Is the timestamp the file's creation time?
No. It is the last modified time provided by your browser, displayed in your device's local time zone.
Are my files uploaded to a server?
All files are processed only in your browser and are never uploaded to a server.