Your address book has the same person three times — and one of the copies is garbled.
ContactFix takes the .vcf file from your iPhone, Android, Google or Outlook export, merges duplicate contacts field-by-field so nothing is lost, repairs damaged entries, and hands you back a clean new file plus a report that proves what it did. Your original file is never overwritten.
Other vendors split this into four separate products — a splitter, a merger, an exporter, a duplicate remover — and sell you each one. ContactFix is the whole job in one $29 tool:
Duplicate detection — by normalised phone (country code unified, so +86 138…, tel:+86138… and bare 138… count as one number), by email + name, across mixed vCard 2.1 / 3.0 / 4.0 files
Lossless merge — fields are unioned, never picked-and-dropped; conflicts are written verbatim into a field-level merge log
Damage repair — quoted-printable / base64 mojibake decoded (UTF-8, GBK and more), missing names rebuilt, version chaos normalised to clean vCard 3.0
Re-check report — the output is re-parsed and re-scanned: duplicate groups remaining, contact-count conservation, fields lost (target: none)
The merge safety report — the part nobody else shows you
Never overwrites. Your export stays byte-identical (we verify this in our own tests with hashes). Output is a new .cleaned.vcf file.
Same email ≠ same person. Two contacts sharing an email but carrying different names are not merged — they land in a "Needs your review" list, with the reason printed.
Every group explains itself. The merge log shows why each group matched (which phone, which email), which value was kept for every field, and what the losing values were.
Before / after — our seeded acceptance test, measured
Before
After ContactFix
Mixed-dialect test file (vCard 2.1 + 3.0 + 4.0)
9 contacts, one person in 3 cards, 2 garbled names, 1 card with no name field
7 contacts, the 3 cards merged into 1 with every field kept, both garbled names decoded, missing name rebuilt
Repairs applied
—
8 (5 encoding decodings, 1 phone-URI normalisation, 1 name rebuilt, 1 name structure synthesised)
Two different people, one shared email
2 contacts a naive merger would fuse
Still 2 contacts — flagged in the review list instead
500-contact file, 40 planted duplicate pairs
500 contacts
460 contacts — exactly the 40 planted groups found, re-check shows 0 duplicate groups, 0 fields lost, 0 new errors
Your original file
untouched
untouched (hash-verified in testing)
Full seeded acceptance run: 36/36 checks passed. The 500-contact file was fixed and re-checked in 0.28 seconds on the test machine.
How it works
Export your contacts as a .vcf file (iPhone, Android, Google Contacts and Outlook all offer this)
Open ContactFix, pick the file — run a scan-only report first if you like; it writes nothing
Or fix: get the cleaned .vcf plus the merge & re-check report, and import the cleaned file wherever you keep your contacts
Windows 10/11. No account, no subscription, no upload — contacts are the most private data you own, and they never leave your computer.