OpenAnyFile
Works
Viewing, inspecting and verifying. You get the full text content with encoding detection. File details, exact byte size and the detected signature are always shown.
How to open a .mht file
The short version: MHT is a MHTML Web Archive from Microsoft / IETF. The longer version — including the quirk that trips most people up — is below, along with a viewer that runs entirely on your own device.
What is a .mht file?
MHTML Web Archive is a text & markup format developed by Microsoft / IETF, first appearing in 1999. It is normally produced by Internet Explorer, Word, Chrome.
A complete web page saved as a single MIME email message: the HTML in one part, every image and stylesheet base64-encoded as further parts.
| Full name | MHTML Web Archive |
|---|---|
| File category | Text & markup |
| MIME type | message/rfc822 |
| Magic bytes (file signature) | 46 72 6F 6D 3A (From:) or MIME-Version |
| Developer | Microsoft / IETF |
| Introduced | 1999 |
| Usually created by | Internet Explorer, Word, Chrome |
| OpenAnyFile engine | plain text reader |
| Opens without upload | Yes — parsed locally in your browser |
Open a .mht file in your browser
OpenAnyFile routes .mht to its plain text reader, which displays the full text content with encoding detection.
- Open the OpenAnyFile opener in this browser — nothing to download or sign up for.
- Drag your .mht file onto the drop zone, click to browse for it, or paste it with Ctrl+V.
- The extension is detected and the file is handed to the plain text reader.
- Your MHT opens on its own viewer page: the full text content with encoding detection.
- Use fullscreen for a closer look, or download the file back out unchanged. Works the same on Windows, macOS, Linux, Android and iOS, because it is just a web page.
What you can and cannot do with it here
Does not work
Editing and re-saving. OpenAnyFile is a reader, not an editor — for changes you still need special software or an equivalent.
No upload, and here is why that matters for {E}
Handing a .mht file to a random conversion site means handing over a copy you cannot get back. OpenAnyFile parses the file locally instead — the same way special software reads it off your disk, except the reader happens to be a web page. Nothing is transmitted, so there is nothing to leak, log or subpoena. It also means it keeps working with your Wi-Fi switched off.
Frequently asked questions about MHT files
Can I open a .mht file without installing special software?
Yes. OpenAnyFile's plain text reader runs in your browser, so you can read a MHT file with nothing installed. You get the full text content with encoding detection. For full editing you still need the original application — this is a viewer, not an editor.
How can I check a file really is a MHT file?
Look at the first bytes rather than the extension. A genuine MHT begins with 46 72 6F 6D 3A (From:) or MIME-Version. Opening the file in OpenAnyFile shows that signature in the file-details panel, so a file renamed to .mht by mistake is easy to spot.
Is it safe to open a MHT file online?
With OpenAnyFile, yes, because nothing is uploaded. The file is read locally through your browser's File API and never leaves your device, so there is no server copy to leak, log or retain. That matters most for the kind of file people are least willing to hand to a random converter site.
What is a .mht file, exactly?
MHTML Web Archive — a message/rfc822 format created by Microsoft / IETF since 1999. A complete web page saved as a single MIME email message: the HTML in one part, every image and stylesheet base64-encoded as further parts.
Does the same viewer handle formats related to MHT?
Yes — the same engine also opens .dat, .srt, .cer, so you can compare related files without switching tools.
Related formats
These open with the same engine, so if you have one of these sitting next to your .mht file, it will open too: