# Create custom duplicate matching rules in Attio

Source: https://neondeerdata.com/docs/videos/duplicate-detection-custom-rules/

Create custom duplicate matching rules for Attio People and Companies. Combine conditions, use related Company attributes, and preview potential matches.

October 26, 20269:44 video

[Create custom duplicate matching rules in Attio](https://www.youtube-nocookie.com/embed/yInnQwuZ-Ys)

[Watch on YouTube](https://www.youtube.com/watch?v=yInnQwuZ-Ys).

Previewing is optional in the current app. You can save a valid custom rule without running a preview.

## In this video

1. [0:00Introduction and prerequisites](https://neondeerdata.com/docs/videos/duplicate-detection-custom-rules/?t=0#player)
2. [0:44Default rules and name similarity sensitivity](https://neondeerdata.com/docs/videos/duplicate-detection-custom-rules/?t=44#player)
3. [1:42Automatic detection versus full scans](https://neondeerdata.com/docs/videos/duplicate-detection-custom-rules/?t=102#player)
4. [2:33Avatar, email, and company matching](https://neondeerdata.com/docs/videos/duplicate-detection-custom-rules/?t=153#player)
5. [3:35Why merging companies can reveal more matches](https://neondeerdata.com/docs/videos/duplicate-detection-custom-rules/?t=215#player)
6. [4:30Provider aliases and redirected email domains](https://neondeerdata.com/docs/videos/duplicate-detection-custom-rules/?t=270#player)
7. [5:36Facebook, LinkedIn, Twitter, and fuzzy names](https://neondeerdata.com/docs/videos/duplicate-detection-custom-rules/?t=336#player)
8. [6:28Create a custom matching rule](https://neondeerdata.com/docs/videos/duplicate-detection-custom-rules/?t=388#player)
9. [7:12Match using related Company attributes](https://neondeerdata.com/docs/videos/duplicate-detection-custom-rules/?t=432#player)
10. [7:52Preview potential matches before saving](https://neondeerdata.com/docs/videos/duplicate-detection-custom-rules/?t=472#player)
11. [8:30Evaluate the preview and save the rule](https://neondeerdata.com/docs/videos/duplicate-detection-custom-rules/?t=510#player)
12. [8:51Duplicate an existing matching rule](https://neondeerdata.com/docs/videos/duplicate-detection-custom-rules/?t=531#player)
13. [9:18Preview warning and wrap-up](https://neondeerdata.com/docs/videos/duplicate-detection-custom-rules/?t=558#player)

## What you'll learn

- Explore built-in rules and name-similarity sensitivity.
- Combine conditions in a custom rule for People or Companies.
- Use attributes from related Company records when matching People.
- Preview potential matches to check false positives, or duplicate an existing rule.

## Written guides

- [Custom rules guide and walkthrough](https://neondeerdata.com/docs/platform/duplicate-detection/matching-rules/#custom-rules-video)

## More Duplicate Detection videos

- [Install Duplicate Detection in Attio](https://neondeerdata.com/docs/videos/install-duplicate-detection/)
- [Find, review, and bulk merge duplicate records in Attio](https://neondeerdata.com/docs/videos/duplicate-detection-scans-and-merges/)

[Browse all video walkthroughs](https://neondeerdata.com/docs/videos/)