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 .mhtml file
MHTML files come from Chrome and Edge 'save as single file', and the usual advice — buy the software that made it — is rarely what you need just to look inside one. This page covers what the format is and how to open it in a browser tab.
What is a .mhtml file?
MHTML Web Archive is a text & markup format developed by IETF, first appearing in 1999. It is normally produced by Chrome and Edge 'save as single file'.
The spelled-out form of .mht with identical content. Chromium browsers write this extension when you save a page as a single file, and can reopen it offline.
| Full name | MHTML Web Archive |
|---|---|
| File category | Text & markup |
| MIME type | message/rfc822 |
| Magic bytes (file signature) | 4D 49 4D 45 2D 56 65 72 73 69 6F 6E (MIME-Version) |
| Developer | IETF |
| Introduced | 1999 |
| Usually created by | Chrome and Edge 'save as single file' |
| OpenAnyFile engine | plain text reader |
| Opens without upload | Yes — parsed locally in your browser |
Open a .mhtml file in your browser
OpenAnyFile routes .mhtml 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 .mhtml 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 MHTML 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.
Your {ext} file stays on your device
The entire pipeline — detection, decoding, rendering — runs client-side. Your browser hands the bytes to a decoder compiled to WebAssembly, the result is drawn to the page, and that is the whole journey. No account is created, no file is stored, and no analytics event carries your filename. This is also why there is no size limit imposed by a server: the only ceiling is your own available memory.
Frequently asked questions about MHTML files
Can I open a .mhtml file without installing special software?
Yes. OpenAnyFile's plain text reader runs in your browser, so you can read a MHTML 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 MHTML file?
Look at the first bytes rather than the extension. A genuine MHTML begins with 4D 49 4D 45 2D 56 65 72 73 69 6F 6E (MIME-Version). Opening the file in OpenAnyFile shows that signature in the file-details panel, so a file renamed to .mhtml by mistake is easy to spot.
Is it safe to open a MHTML 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 .mhtml file, exactly?
MHTML Web Archive — a message/rfc822 format created by IETF since 1999. The spelled-out form of .mht with identical content. Chromium browsers write this extension when you save a page as a single file, and can reopen it offline.
Does the same viewer handle formats related to MHTML?
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 .mhtml file, it will open too: