Contacts duplicate cleaner

How matching works: two contacts group together when they share an email ignoring case and surrounding spaces, or a phone whose digits are identical and which agrees on whether a country code is present, or a full name identical after Unicode normalization, lowercasing, and space folding. Emails never lose dots or plus tags, and numbers under 7 digits never match, because short extensions would collide constantly. Groups are transitive, so A sharing an email with B and B sharing a phone with C forms one group of three. A merge keeps every phone, email, address, website, note, and labeled custom field once across the group, with each value droppable, and takes single values from the member you pick. Apple item groups are renumbered so labels stay attached to the right values, and fields the tool does not know ride along from the first member. The rebuilt file is re-parsed before download so the contact count is measured, not assumed. This tool never signs in to iCloud and never uploads your file: export the .vcf from iCloud Contacts, clean it here, then delete the old contacts in iCloud and import the cleaned file. A service that signs in and rewrites your account for you is outside what a local page can do.