Free online MAB to CSV converter
Export legacy Thunderbird contacts to CSV for editing or importing into other software.
Convert MAB to CSV online - free
Column separator
Excel in many European languages expects a semicolon; with commas it puts everything into one column.
Character encoding
If Excel shows broken accents, choose UTF-8 with BOM or the Windows code page.
Your file is processed instantly and deleted as soon as you download it.
Import a file from a URL
Paste a direct link to the file. We download it to our server and it is converted exactly like an upload.
How it works
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Upload your .mab file
Click to browse to select your file you want to convert or simply drag & drop your file into selected area.
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Perform .mab to .csv conversion
After successful file upload, click to convert when you are ready.
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Download converted .csv file
Conversion result is ready to download.
How to convert mab to csv file
- Contacts and address books
- No ratings yet.
Some contact managers and import workflows accept CSV but cannot read the legacy address-book database used by older Thunderbird profiles. Exporting to CSV also makes contact fields editable in spreadsheet software.
What the MAB format is
MAB is a Mozilla address-book database format based on Mork. Older Mozilla Thunderbird and Netscape Communicator versions used it for contacts; Thunderbird profiles commonly contain abook.mab (the personal address book) and history.mab (collected addresses). Thunderbird 78 and later use SQLite for address books, so MAB files are mainly found in older profiles and backups.
What the CSV format is
CSV represents tabular data as text, with rows for contacts and separated fields for values such as names, email addresses, and phone numbers. Spreadsheet and contact software widely support it, but the receiving program may require field mapping. Separators and character encoding affect how values appear when the file is opened or imported.
Convert online on 101convert.com
- Open the MAB-to-CSV converter on 101convert.com and upload the file. You can add several files for batch conversion; the page displays the per-file size limit.
- Before converting, choose the column separator and character encoding if needed.
- Run the conversion and download the CSV file.
Convert offline with desktop software
Mozilla Thunderbird can export MAB through a pre-78 release, which uses the legacy address-book format and runs on Windows, macOS, and Linux. Older releases are unsupported and may not run on current systems; use a separate profile, never your everyday Thunderbird profile.
- Install a pre-78 Thunderbird release and create a new, disposable profile in Profile Manager. Do not open a newer Thunderbird profile with the older release.
- Start the disposable profile once, open Help → Troubleshooting Information → Profile Folder, then quit Thunderbird.
- Back up the MAB file. For a personal address book, copy it into the profile folder as
abook.mab, replacing only the disposable profile's file. Start Thunderbird and confirm the contacts appear in the Address Book. - In the Address Book, select the address book and choose Tools → Export. Choose CSV as the output format and save the file.
Compatibility and data checks
CSV stores rows and fields, not MAB's address-book database structure; mailing-list relationships and custom fields may not transfer as structured data. Check names, email addresses, phone numbers, and non-ASCII characters after export, and confirm the receiving program uses the same separator and compatible encoding. Uploading a contact file exposes its personal data to the online service; use the offline method if that is unacceptable.
MAB vs CSV: format comparison
How the MAB and CSV formats compare on the properties that matter most for this conversion.
| Property | .MAB Mozilla Address Book file | .CSV Comma-Separated Values |
|---|---|---|
| Plain-text readable | Yes | Yes |
| Data types | Typed | Typed |
| Nested structures | Yes | No |
| Formulas | No | No |
| Multiple tables or sheets | No | No |
| Typical file size | Small | Small |
| Open standard | No | Yes |
| Best used for | Sharing and distribution | Data exchange |
| Developer | Mozilla Foundation | — |
| MIME type | — | text/csv |
Information about file extensions and file types is provided by File-Extensions.org
Suggested software and links: mab to csv converters
Frequently asked questions
Is the MAB to CSV converter free?
Yes, converting MAB to CSV on 101convert.com is completely free. No registration, email address or installation is required. If you need a higher file size limit or want to convert more files at once, see our plans.
How large can my MAB file be?
You can upload MAB files up to 3 MB and convert up to 3 files at once in a single batch. With a paid plan the limit is up to 15 MB per file and 100 files at once, see our plans.
What happens to my uploaded files?
Files are processed automatically and deleted from our servers within a few minutes after conversion. We never view or share your files.
Do I need to install any software to convert MAB to CSV?
No. The MAB to CSV conversion runs entirely online in your browser and works on Windows, Mac, Linux, Android and iPhone.
Did the conversion fail?
In most cases, the cause is an incorrect file format. Please upload a valid MAB file for this MAB to CSV conversion. Occasionally, the issue may be on our side. We analyze recurring conversion failures and disable or fix the converter if we detect a defect.