Data deduplication is the process of finding records that represent the same person, company, product, or other entity, then removing redundant records or merging their useful values.

The records do not need to be identical. These rows can describe the same contact while containing complementary or conflicting data:

jane@example.com | Jane Carter | (empty)
jane@example.com | J. Carter   | +1 415 555 0199

Deduplication has two separate decisions

First, decide whether records match. Then decide what to do with the group.

1. Find duplicate records

Choose properties that identify one record and configure how they are compared:

  • Exact matching for IDs, codes, and already normalized values.
  • Smart matching for harmless formatting differences in emails, URLs, phone numbers, text, and company names.
  • Distance matching for spelling differences and typos.
  • Phonetic matching for names that may sound alike.

Several properties can reduce false matches, but requiring too many values can hide duplicates when one field is empty. See multi-column deduplication for this tradeoff.

2. Process each duplicate group

After matching, you can:

  • Remove extra rows when they add no useful information.
  • Merge complementary values into one record.
  • Resolve conflicting values with a field rule or manual review.
  • Skip uncertain groups.

⚠️ Similar does not always mean duplicate

A fuzzy or phonetic match creates a candidate group. Review weak identifiers such as names before deleting or merging records.

Deduplication within or across lists

Single-list deduplication finds duplicate records inside one table. Cross-list deduplication compares separate files or collections, often to remove contacts from an incoming list when they already exist in a CRM.

Read cross-list deduplication for the distinction.

Datablist's Duplicates Finder supports Exact and Smart matching on the Free plan, advanced fuzzy and phonetic algorithms on paid plans, group review, removal, merge previews, and conflict resolution.

Follow the tested list deduplication workflow, or open the Duplicate Finder reference for every algorithm and setting.