GUIDE
What X-Properties Mean in a VCF File
X-properties are non-standard or vendor-specific properties. They may contain useful metadata, but they are also a common source of compatibility differences.
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What you should know
X-properties are non-standard or vendor-specific properties. They may contain useful metadata, but they are also a common source of compatibility differences.
Before you begin
- Keep an untouched copy of the source export.
- Work on a small sample before changing a complete address book.
- Review the downloaded file before importing it elsewhere.
Preserve unknown data when possible
A converter should keep unrecognized properties in the source archive or warn before dropping them. Do not rename an X-property into a standard field without knowing its semantics.
Use a destination fixture
Export one contact from the destination application and compare its custom properties with the source. This reveals whether the platform uses a stable extension or a one-off internal key.
- Validate the copied VCF.
- List X-properties and their values.
- Compare a destination-generated sample.
- Choose preserve, remove, or map with an explicit rule.
Privacy review
Custom properties can include CRM IDs, sync tokens, or internal notes. Remove them from a public card when the recipient does not need them.
Questions people ask
Does What X-Properties Mean in a VCF File change the original file?
No. The browser works with the selected copy and creates a separate download. Keep the original export as your rollback point.
What should I verify after What X-Properties Mean in a VCF File?
Compare counts and representative fields, validate the generated copy, and test a small import before processing a full address book.