How long should I run a new ad before judging it?
Leave a new ad alone for at least 5 to 7 days. Meta's system learns from roughly 50 results a week, so judging on day one tells you almost nothing. Every significant edit restarts that learning, which is why constant fiddling keeps costs high.
ShoaibUpdated 3 min read
Why does Meta need time?
Meta's help centre explains that after a new ad set or a significant edit, delivery goes through a learning period, and an ad set becomes "Learning limited" when it's unlikely to get around 50 optimisation events in a week.
An "optimisation event" is whatever you asked for: a purchase, a lead, a chat.
What does that mean for a small budget?
If your win is a purchase and you get 5 a week, Meta never finishes learning, and costs stay unstable. Two fixes:
- Optimise for something more frequent at first, such as chats started rather than purchases.
- Put your budget in fewer ad sets instead of spreading it thin.
What resets the learning?
Per Meta's help centre, significant edits include changes to:
- the audience or targeting
- the budget or bidding
- the creative (image, video, text)
- the optimisation event
A simple rule to follow
| Day | What to do |
|---|---|
| 1–2 | Don't touch it. Numbers swing wildly |
| 3–5 | Check cost per result, not likes |
| 5–7 | Decide: keep, adjust one thing, or stop |
| After | Change one thing at a time |
If you want to compare two versions properly, use a test instead of guessing: see how to test two ads properly.
Tired of restarting from zero? Our Meta Ads service runs the testing calendar for you.