Bid optimization explained
The Optimize Bids feature in the target manager analyzes each target's performance and calculates a new bid based on how it's performing relative to your Target ACOS. Instead of adjusting bids manually, you select your targets, click Optimize Bids, review the recommendations, and apply the ones you want.
This page covers the manual Optimize Bids button in Target Manager — you trigger it, you pick the preset, you approve the changes. For the daily background automation that runs on campaigns you've enabled it on, see Automated bid optimization.
The four conditions
AdTrix checks each target against four conditions in priority order. The first condition that matches determines the new bid — only one condition applies per target.
| Priority | Condition | What it means | What happens |
|---|---|---|---|
| 1 | High ACOS | Spending too much per sale | Bid decreases |
| 2 | High spend, no sales | Money going out, nothing coming back | Bid decreases |
| 3 | Low ACOS | Strong performer with room to grow | Bid increases |
| 4 | Low visibility | Not getting enough traffic | Bid increases |
Targets that fall between your High ACOS and Low ACOS thresholds are in the "sweet spot" — their bids stay unchanged.
High ACOS
When it triggers: Your target's ACOS is above the High ACOS threshold. With the default threshold of 1.2x, a target with a 30% Target ACOS triggers this condition when its ACOS exceeds 36% (30% x 1.2).
Formula:
New Bid = Revenue per Click x Target ACOS x Placement Modifier
Revenue per Click (RPC) is your Sales divided by Clicks — how much revenue each click generates on average. The Placement Modifier accounts for any placement bid adjustments on your campaign (such as Top of Search or Product Pages multipliers). If you haven't set any placement adjustments, the modifier is 1.0 and has no effect.
Example:
Your keyword "wireless charger" has a Target ACOS of 30% and a Top of Search placement modifier of 1.5x. Over the last 14 days it earned $200 in sales from 100 clicks, so its Revenue per Click is $2.00. Its current ACOS is 45% — well above the 36% threshold.
New Bid = $2.00 x 30% x 1.5 = $0.90
Without the placement modifier, the bid would be $0.60. The modifier adjusts for the fact that top-of-search clicks tend to convert better and are worth bidding more for.
If the current bid was $1.10, that's an 18% decrease — within the default 20% max decrease safety limit, so the full change applies.
High spend, no sales
When it triggers: Your target has $0 in sales AND its total spend exceeds your target cost-per-acquisition (Target ACOS x average order value). With a 30% Target ACOS and a $50 average order value, this triggers when spend exceeds $15.
Formula:
New Bid = Estimated Revenue per Click x Target ACOS x Placement Modifier
Since there are no sales to calculate actual Revenue per Click, AdTrix estimates it using the average order value and a benchmark click-to-conversion rate for similar targets. The Placement Modifier works the same way as in the High ACOS condition — it adjusts for your campaign's placement bid adjustments.
Example:
Your keyword "phone stand adjustable" has spent $18 with 15 clicks but zero sales. Your Target ACOS is 30% and similar products sell for $50 on average, making your target cost-per-acquisition $15. Since $18 exceeds $15, this condition triggers. No placement adjustments are set (modifier = 1.0).
AdTrix estimates what revenue per click would look like if the target eventually converts, using category benchmarks. If the benchmark suggests 100 clicks per conversion on average:
Estimated RPC = $50 / (15 + 100) = $0.43
New Bid = $0.43 x 30% x 1.0 = $0.13
Low ACOS
When it triggers: Your target's ACOS is below the Low ACOS threshold AND it has at least one sale. With the default threshold of 0.8x, a target with a 30% Target ACOS triggers this condition when its ACOS is below 24% (30% x 0.8).
Formula:
New Bid = Current Bid x 1.20 (20% increase)
This is a flat percentage increase — the target is already performing well, so AdTrix nudges the bid up to capture more traffic while staying efficient.
Example:
Your keyword "USB-C cable 6ft" has a 12% ACOS against a 30% Target ACOS. It's performing well below your target — there's room to bid higher and win more impressions.
Current bid: $0.50 → New bid: $0.50 x 1.20 = $0.60
Low visibility
When it triggers: Your target's click count is below the Low Visibility threshold relative to what similar targets typically receive. With the default threshold of 0.9x, if the benchmark is 50 clicks, this triggers when your target has fewer than 45 clicks. This condition is skipped if the target's ACOS is already in the acceptable range between your Low and High ACOS thresholds.
Formula:
New Bid = Current Bid x 1.10 (10% increase)
A smaller increase than Low ACOS — the goal is to get enough traffic to measure performance, not to scale aggressively.
Example:
Your keyword "laptop sleeve 14 inch" only got 5 clicks while similar keywords typically get 50+. A small bid boost helps it compete for impressions.
Current bid: $0.40 → New bid: $0.40 x 1.10 = $0.44
Safety limits
Safety limits prevent any single optimization round from making drastic changes to your bids. You can adjust all of these in bid settings.
- Max increase % (default 20%) — Even if the formula calculates a much higher bid, the increase is capped. A $0.50 bid can only go up to $0.60 in one round.
- Max decrease % (default 20%) — Same concept for decreases. A $1.00 bid can only drop to $0.80 in one round. For decrease conditions, AdTrix uses the lower of your current bid or your actual cost-per-click as the baseline, so the decrease is meaningful even if your bid is much higher than what you're actually paying.
- Bid ceiling (default 2x) — For increase conditions, the new bid can't exceed 2x a benchmark price. For Low Visibility, this is based on the typical cost-per-click for similar targets. For Low ACOS, it's based on Revenue per Click x Target ACOS. This prevents overbidding on targets where the formula suggests a higher bid than the market supports.
- Minimum bid — Amazon's marketplace minimum (usually $0.02 for Sponsored Products) is always enforced.
- Maximum bid — Amazon's per-marketplace, per-campaign-type maximum is always enforced.
Optimization works best with small, repeated adjustments rather than one large swing. If a bid needs a bigger change, it'll get there over successive rounds. This protects you from volatile data — a single bad week shouldn't halve your bids overnight.
Presets
Presets give you a one-click starting point. Pick the one that matches your current advertising goal, and all thresholds and limits are set automatically.
Control ACOS
Best when profitability is your top priority. This preset triggers a bid decrease the moment ACOS reaches your target — no tolerance for overspending. Decreases are aggressive (up to 100%) while increases are cautious (10% max per round). Use this for mature campaigns where you know your margins and want to protect them.
Balanced
The default for most sellers. Gives equal room for increases and decreases (20% each) and allows a 20% buffer above your Target ACOS before cutting bids. This gives targets time to stabilize without letting spending get out of control.
Scale Faster
For sellers prioritizing growth over efficiency. Allows up to 30% bid increases per round and tolerates ACOS up to 1.5x your target before reducing bids. Use this when you're launching new products, entering new markets, or want to capture more market share and can accept temporarily higher ACOS.
Scale Aggressive
Maximum growth mode. Tolerates ACOS up to 2x your target, allows 40% bid increases, and only decreases bids by 10% per round. Use sparingly — this preset prioritizes volume over efficiency and is best for short-term ranking pushes or product launches where visibility matters more than profitability.
Preset comparison
| Setting | Control ACOS | Balanced | Scale Faster | Scale Aggressive |
|---|---|---|---|---|
| Decreases bid when ACOS exceeds | 1.0x target | 1.2x target | 1.5x target | 2.0x target |
| Increases bid when ACOS is below | 0.5x target | 0.8x target | 0.9x target | 0.95x target |
| Max bid increase per round | 10% | 20% | 30% | 40% |
| Max bid decrease per round | 100% | 20% | 15% | 10% |
| Best for | Protecting margins | Most sellers | Growth phase | Product launches |
Start with Balanced. After 2-4 weeks, review your results and switch to a more aggressive or conservative preset based on how your ACOS and sales are trending.
ACOS mode
Bid optimization needs a Target ACOS to calculate new bids. You can choose where that target comes from:
-
Campaign Target ACOS (default) — Each target uses the Target ACOS set on its parent campaign. This is best when different campaigns have different goals — for example, branded campaigns at 15% and discovery campaigns at 40%.
-
Custom ACOS — A single ACOS value applied to every target in the profile, regardless of campaign. This is best when you want a uniform strategy across all your campaigns.
If you haven't set a Target ACOS on your campaigns yet, AdTrix defaults to 35%. You can set a campaign's Target ACOS by editing the Target ACOS column in the campaign manager or target manager.
Advanced threshold settings
If the presets don't match your exact strategy, you can fine-tune individual thresholds in the Advanced section of bid settings:
| Threshold | What it controls | Default |
|---|---|---|
| High ACOS threshold | How far above Target ACOS triggers a decrease | 1.2x |
| Low ACOS threshold | How far below Target ACOS triggers an increase | 0.8x |
| Low visibility threshold | How far below the click benchmark triggers a boost | 0.9x |
| High spend threshold | How much spend (relative to target CPA) triggers a decrease for targets with no sales | 1.0x |
Lowering the High ACOS threshold makes the optimizer more aggressive about cutting overspending bids. Raising the Low ACOS threshold makes it more willing to increase bids on efficient targets. Most users won't need to adjust these — the presets handle it.
What's next
- Automated bid optimization — how the daily background automation works
- Managing targets — view, filter, and edit your targets
- Your first optimization — set up automated bid optimization
- Understanding ACOS — learn what ACOS means and how to set goals