What is File Size Analyzer?

File Size Analyzer lets you drop multiple files to compare their sizes side by side. See a visual breakdown of each file's contribution to the total, identify the largest files, and sort by size — all without uploading anything.

Drop in dozens of files at once and the analyzer adds up bytes, flags the heaviest item, and shows percentages relative to the whole batch. There's no upload step — everything runs on your device, so even confidential documents stay private. Sort by size to spot the megabyte culprits before sending a download link or archive.

How to use

1. Step 1 — Drop or select multiple files from your device.
2. Step 2 — View the size breakdown chart showing each file's relative size.
3. Step 3 — Sort by size to quickly identify the largest files and copy the summary.

When to use

• Trimming a project folder before zipping and emailing it to a coworker.
• Auditing a Downloads folder to find which old files are eating disk space.
• Comparing exports from different image tools to pick the smaller version.

Result

Analyzing a project folder: drop 8 files to see that video.mp4 (45 MB) dominates at 78% of total size, while all text files together are under 1 MB.

FAQ

Can the analyzer measure a whole folder, or only individual files?

Drag a folder from your file manager and most modern systems will pass through every file inside. The tool then totals them all. Empty subfolders aren't reported because there's nothing to measure.

Does dropping a 4 GB video upload it somewhere?

No. To total the sizes the page only needs each file's name, byte length, and type, so for plain size analysis nothing is read into memory at all. Computing the SHA-256 checksum does read the full contents, but that happens entirely on your device — no bytes are ever copied or sent anywhere. That's why even huge files stay private and feel near-instant.

Why do my reported sizes differ from what the OS shows?

Operating systems sometimes report size on disk, which includes allocated cluster padding. The analyzer reports the actual byte count of the file's contents — the number that matters for email attachments or zip archives.

What's the largest number of files I can drop in one go?

There's no hard cap. Hundreds work fine. Performance starts to noticeably slow when you cross several thousand entries because the table re-renders on every sort change.

Can I save the size breakdown to a file or just copy it?

Three ways. The Download button saves a plain .txt report — file list, total, average, largest and smallest — handy to archive or email. The CSV button exports a spreadsheet-ready file with a row per item (name, extension, exact byte size, readable size, type, and percent of total), perfect for opening in Excel or Google Sheets. The Copy button drops a readable summary on your clipboard for a quick paste into an email or chat.

Related Tools