EditSafely

Check If an Image Is a BMP

Read a file's real bytes to confirm whether it is a true BMP. Runs entirely in your browser, so your data never leaves your device.

Input

Drop a file here, or click to browse

Files never leave your device

Output

The result appears here as you type.

How to use Check If an Image Is a BMP

  1. 1. Upload the file in question. Drop in the file you suspect might not really be a BMP, regardless of what its extension claims. The tool reads its raw bytes rather than trusting the filename.
  2. 2. See the header check. The tool looks at the first bytes for the BM signature that every true bitmap file starts with, then reports whether the file is genuinely a BMP or something else entirely.
  3. 3. Read the verdict. Copy or note the yes-or-no answer, which also names the actual format detected when the file was mislabeled, such as a GIF or PNG saved with a .bmp extension.

When to use Check If an Image Is a BMP

Check If an Image Is a BMP inspects a file's actual magic bytes instead of trusting its extension, so it catches files that were renamed or mislabeled. Use it whenever a pipeline or upload form needs to be certain a file is a real bitmap before processing it.

  • Validating an upload before processing. A batch-processing script only handles true BMP bitmaps and would crash on a mislabeled file. Checking each upload first avoids feeding the wrong byte layout into a strict decoder.
  • Auditing a downloaded asset pack. A design asset archive has files with .bmp extensions from an unreliable source. Running each through the check confirms which ones are genuine bitmaps before importing them into a project.
  • Debugging a broken image import. An image viewer refuses to open a file that is supposedly a bitmap. Checking its real signature quickly reveals it was actually saved as a GIF with the wrong file extension.

Examples

Renamed file

Input

bitmap.bmp (actually a GIF)

Output

No — it looks like a GIF file.

About the Check If an Image Is a BMP tool

Check If an Image Is a BMP runs as plain JavaScript in your browser tab, with no server behind it. Read a file's real bytes to confirm whether it is a true BMP. Whatever you put in stays on your device from start to finish.

The tool is part of EditSafely's Image Tools section, 200 single-purpose utilities built around the same idea: open the page, get the result, keep your data to yourself.

There is nothing to configure. Provide the input and the result appears on its own. A worked example further down the page shows exactly what the tool produces for a real input.

That local-first design has practical benefits beyond privacy. The tool keeps working on a flaky connection once the page has loaded, results are instant because nothing round-trips to a server, and it is safe to use with confidential material.

Frequently asked questions

Does Check If an Image Is a BMP cost anything?

Yes, it is completely free. All 2,658 tools on EditSafely work without an account, a subscription or usage limits.

Are my files uploaded to a server?

No data leaves your device. The whole tool is JavaScript that runs inside your browser tab, so there is no upload, no server-side processing and no log of what you did. If you disconnect from the internet after the page loads, it keeps working.

Which files does Check If an Image Is a BMP accept?

It accepts images in any common format (PNG, JPG, WebP, GIF and more). There is no file size cap imposed by a server; very large files are limited only by your device's memory.

Do I need to sign up or install anything?

Nothing to install and no account needed. Open the page in any up-to-date browser, including on a phone or tablet, and the tool is ready.

How do I use the result?

The output panel has a one-click copy button, and you can keep refining the input while you work; the result updates in place as you type.

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