Custom Rules

Custom rules let you manually allow, block, or redirect domains.

This is where you can fine-tune a profile without turning it into a giant exception list that is impossible to maintain.

Allowlist

An allowlist contains domains you want to permit even if a filter would otherwise block them.

Use allowlist entries when:

  • A website is being blocked incorrectly
  • An app needs a specific API or CDN domain
  • A trusted service is being caught by a broad list

Important: keep the allowlist as narrow as possible.

A good allowlist entry is:

  • Specific
  • Necessary
  • Well-documented
  • Easy to review later

Denylist

A denylist contains domains you want to block regardless of other filters.

This is helpful when:

  • You know a specific domain is unwanted
  • A website is not covered by your active filters
  • You want a personal rule for a domain you do not trust

Use folders

Folders help keep rules organized.

Useful folder names include:

  • Allowlist
  • Denylist
  • Work
  • Kids
  • Temporary
  • Exceptions

This helps a lot when you later need to audit or clean up rules.

Wildcards

Wildcards can apply a rule to multiple subdomains.

Example:

*.example.com

This may affect several subdomains, including:

www.example.com
api.example.com
cdn.example.com

Use them carefully. Broad wildcards can affect more than you intended.

Best practice: narrow exceptions

If a website is broken, do not immediately allow a whole domain family.

Instead:

  1. Check the Control D query log
  2. Identify the exact blocked domain
  3. Allow only the necessary domain
  4. Re-test the site or app
  5. Keep the exception documented

This is much safer than allowing broad categories or random domains.