LDIF to CSV: convert a Thunderbird or LDAP address book to a spreadsheet
In short: Turns an .ldif file from Thunderbird, macOS Contacts or an LDAP directory into a CSV: one row per person with name, every email and phone, company, title and address; base64 (::) values decoded, folded lines joined, mailing lists counted and skipped. Limit: Values that point at a file (attr:< url) can't be read in the browser; they're counted.
Upload or paste the .ldif file and each entry becomes a CSV row: cn, givenName and sn as names, mail and mozillaSecondEmail as email columns, telephoneNumber, mobile and homePhone as phones, plus company, title and address. Base64 values (written attr::) are decoded, so accented names come through. Mailing-list entries are counted and skipped. Choose simple columns or Google Contacts import headers.
Price: this tool is free. Checking a whole email list is from $9/mo, and the first 100 checks are free with Google, no card. See pricing
Contacts with several emails or phones get numbered columns. Mailing lists are counted, not converted.
Sample result
An LDIF address book became 3 CSV rows; the mailing list was skipped.
- Contacts
- 3
- Emails
- 3
- Mailing lists skipped
- 1
What this means for you
Base64 names are decoded, so Jörg Müller comes through with his accents.
- Thunderbird and LDAP LDIF
- Base64 values decoded
- Every email and phone kept
- Simple or Google Contacts CSV
- LDIF
- Thunderbird
- CSV
By SimpleVerifier Team · Last updated · Runs in your browser; nothing you paste is sent to us
How do I check the addresses before I email them?
- Download the CSV here.
- Upload it at /verify. Every address gets a live mailbox check, and valid, risky and invalid download as separate files. The first 100 email checks are free with a Google sign-in, no card.
- Import or send to the valid file only.
How do I turn an LDIF file into a CSV?
- Export the address book as LDIF: in Thunderbird, open the Address Book, right-click the address book and choose Export, then LDIF; from an LDAP server, use your directory's export or ldapsearch output.
- Upload the .ldif file here, or paste its text.
- Pick the CSV columns: simple (full_name, email_1, phone_1 …) or Google Contacts import headers.
- Download the CSV, or copy every email address.
Example
- You enter
- A Thunderbird LDIF file with 3 people and a mailing list: one with a second email (
mozillaSecondEmail), one whose name is stored as base64 (cn:: SsO2cmcgTcO8bGxlcg==), one with only a phone. - You get
- 3 CSV rows: Ana Silva with 2 emails, company and title; Jörg Müller decoded from base64 with a mobile and
Berlin, DE; Leo Park with a phone and no email (noted). The mailing list is counted and skipped. - Limits
- Reads RFC 2849 LDIF. Runs in your browser with no row cap; an uploaded file can be up to 25 MB.
What is an LDIF file?
LDIF (LDAP Data Interchange Format, RFC 2849) is a plain-text format for directory entries. Each entry starts with a dn: line and is a block of attribute: value lines, separated from the next entry by a blank line. A line starting with a single space continues the line above, and a double colon (cn:: …) means the value is base64, which is how names with accents or non-Latin letters are stored.
Thunderbird writes its own attribute names alongside the standard ones: mozillaSecondEmail for the second address, mozillaNickName, and mozillaHome… fields for the home address. All of these are mapped to columns.
Who uses this tool, and for what?
- People leaving Thunderbird
- Move an address book to Gmail or Outlook through a Google Contacts CSV.
- IT admins
- Turn an LDAP or directory dump into a spreadsheet of names, emails and phones.
- Small businesses
- Rescue a client list from an old desktop mail backup before a send.
What can’t this tool tell you?
- Values that point at a file (attr:< url) can't be read in the browser; they're counted.
- Custom attributes beyond the common person and Thunderbird ones are left out.
- Photos (jpegPhoto) are not converted.
- It can't tell which addresses still have a working inbox.
Common questions
- Can't Thunderbird export CSV directly?
- It can. LDIF is still what many old backups, macOS Contacts exports and LDAP directories give you, and it carries every address an entry has.
- What happens to mailing lists?
- Entries with objectclass groupOfNames are mailing lists; their members are already their own entries, so lists are counted and not turned into rows.
- Is my address book uploaded?
- No. It is read in your browser and nothing is sent anywhere.
Sources
A tidy list can still be full of dead addresses.
Extracting, deduplicating and syntax checks all work on the text of an address. None of them can tell whether the mailbox exists. Only the server that hosts it can answer that, through an SMTP check, and that is what the paid product does.
- Upload the cleaned file as it is: CSVs up to 100,000 rows
- A real SMTP mailbox check on every row, with catch-all detection
- Small list? Starter at $9/mo covers 2,500 emails a month, cancel anytime
Plans from $9 a month, cancel anytime, no contract. Sign in with Google and your first 100 email checks are free, no card. The free tools stay free either way.