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MBOX viewer

List every message in an mbox export — sender, date and subject — without a mail client.

10 / 10 free files today

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MBOX to EMLSplit an mbox export into one .eml file per message, ready to open individually.EML viewerOpen a saved email and read it — sender, date, subject and body — with no mail client.ICS viewerOpen a calendar invitation or export and read its events before importing anything.VCF viewerOpen a .vcf file and read the contacts it holds, without importing them anywhere.Spreadsheet viewerOpen and read an .xlsx, .xls, .ods or Numbers file without a spreadsheet program.Extract email attachmentsPull every attachment out of a saved .eml message and download them separately.EML to HTMLSave the HTML part of an email as a standalone page you can open in a browser.EML to textPull the readable text out of a saved email, decoding quoted-printable and base64 bodies.

MBOX viewer is free to use as often as you like, directly from this page. Its place is under Email; MBOX to EML and EML viewer answer the questions closest to this one.

How to use it

  1. Open the tool — no signup or install needed.
  2. Enter your input or adjust the available options.
  3. Get your result instantly, then copy or download it.

Frequently asked questions

What does MBOX viewer do?

List every message in an mbox export — sender, date and subject — without a mail client.

When would I actually use this?

Reading a message exported from a mailbox you no longer have open, pulling the attachments out of one, and turning an mbox export — one long file holding a whole folder — back into messages you can open one at a time.

What is the most common mistake?

Reading a raw header as if it were text. Any header may be encoded, so a subject with accents arrives as base64 and shows as gibberish taken literally. The matching trap is in the body: a line that happens to begin "From " is not a message boundary, and treating it as one cuts the message in half without changing the message count.

How is MBOX viewer different from MBOX to EML?

They sit next to each other but answer different questions. MBOX to EML: split an mbox export into one .eml file per message, ready to open individually. Pick whichever matches what you're starting from — both are free.

Is there a tool for the next step?

EML viewer is the closest one after this: Open a saved email and read it — sender, date, subject and body — with no mail client.

Where do the figures come from?

Messages are parsed against the mail and MIME specifications, in the browser, so nothing is sent anywhere — which matters more for mail than for most files. The mbox separator is matched on its full shape, sender and date together, rather than on the two words it starts with.

Further reading

All guides →
ExplainerAn .mbox Is Messages Glued End to End, and the Glue Is a LineOne file, thousands of messages, separated by a line beginning From. The format has one famous weakness, and it is the reason a message can lose its ending without anything reporting an error.How-toSplitting a Mail Archive Into One File per MessageAn .mbox is one enormous file your operating system cannot search. Turn it into .eml files and every message becomes something your machine indexes, your mail client opens and you can delete one at a time.ExplainerEmail HTML Is Twenty Years Behind the Web, on PurposeNo stylesheet, no script, layout built from nested tables and styles written on every single tag. Knowing why explains what an exported HTML file will and will not look like.ExplainerWhy Your Subject Line Arrives as =?UTF-8?B? and a String of LettersMail headers are allowed to carry ASCII only, so an accented subject is encoded before it travels. Two encodings are in use, both start with =?, and decoding them is the whole difference between a readable message and a wall of symbols.ExplainerAn Attachment Grows by a Third Inside the EmailMail carries files as text, three bytes written as four characters. A 10 MiB attachment occupies 13.68 MiB of the message, which is why a 25 MB limit really means about 18 MiB of files.How-toOpening an .eml File Without Telling the SenderA saved message is a text file you can read anywhere. The catch is that opening it in something that loads remote images announces the moment you did — which is what a tracking pixel is for.