Test files › Email › mailbox.mbox
Sample MBOX file (mailbox)
An mbox archive of three messages, the format Gmail Takeout, Thunderbird and Apple Mail all export. Includes a body line beginning with "From " that has been escaped to ">From ".
↓ Download mailbox.mbox| Filename | mailbox.mbox |
| Format | MBOX |
| Size | 1.1 KB (1,090 bytes) |
| MIME type | application/mbox |
| SHA-256 | 85ff4064c9efec3a74d56ef8d3abc2d064f32dd9402bde713e1ff70a216f54da |
What this file catchesmbox splitting. A parser that splits on every line starting with "From " will corrupt the third message; one that never unescapes ">From " will silently alter the body text.
Handle it in code
Each snippet below was run against this exact file with Python 3.14.4 and Node 24.15.0 when this page was built, and the output shown is what it printed.
Python
The standard mailbox module reads mbox files message by message, handling the "From " separator lines for you.
import mailbox
box = mailbox.mbox("mailbox.mbox", create=False)
for i, msg in enumerate(box, 1):
print(f"{i}. {msg['From']} | {msg['Subject']}")
print(len(box), "messages")
box.close()Run against this file, it prints: 1. Ava Stone <ava.stone@example.test> | Quarterly report
2. Liam Vargas <liam.vargas@example.test> | Re: Quarterly report
3. Ava Stone <ava.stone@example.test> | Tricky body
3 messages
Related guides and tools
Sample EML and MSG email filesReserved domains for test emailCharacter encodingsCheck a file's real typeVerify its SHA-256
Download & verify
curl -fsSL -o "mailbox.mbox" "https://files.hexaqa.com/email/mailbox.mbox"
curl -fsSL "https://files.hexaqa.com/email/mailbox.mbox" | sha256sum
# expect: 85ff4064c9efec3a74d56ef8d3abc2d064f32dd9402bde713e1ff70a216f54da