A Practical Guide to Third-Party Budgets
Limits on how much third-party script weight and execution time a site allows.
Marcus Adeyemi
At a glance
- Ownership third-party tags often have no technical owner
- Impact third parties can dominate main thread time
- Governance adding tags needs a review process
- Removal unused tags stay unless someone checks
Why it matters
Why it matters: Third-party code is added by marketing and product teams with no single owner, and it accumulates invisibly.
Best practice
- Inventory every third-party script and its owner
- Set a budget for third-party weight and execution
- Require review before new tags are added
- Audit and remove unused tags quarterly
- Load non-critical tags after interaction
Common pitfalls
Watch out for:
- Tags added without review
- Scripts with no named owner
- Inventories that are never revisited
- Third parties loading before content
When to call in a specialist
Bottom line Bring in help when tag managers slow the site.
Where this comes from
- web.dev — Third-party JavaScript
- Google Analytics Help — Tag management
The figures and practices above come from the sources listed.
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