Top-of-Search Optimizer (TOSO)

Understanding the importance of Top-of-Search on Amazon and how to use Perpetua's TOS Optimizer with your keyword boosts

Andrea Mamone avatar
Written by Andrea Mamone
Updated this week

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What is Top-of-Search?

Top-of-Search, or simply TOS, is the placement where your ads (Sponsored products) appear on the search results page on Amazon. TOS refers to the first row on the first page of search results, and you will be able to spot these placements by seeing the “Sponsored” tag appearing just below the product image.

Why is Top-of-Search Important?

When your ads gain the Top-of-Search placement of the search results page on Amazon, you maximize the visibility of your ads and increase the chance of converting.

The Top-of-Search results on Amazon are considered important for several reasons:

1️⃣ Visibility
The top search results receive the highest visibility and exposure to potential customers. Being at the top increases the chances of your product being seen and clicked on by users, which can lead to higher sales.

2️⃣ Credibility and Trust
Shoppers often associate top search results with popular and reliable products, which can give a sense of credibility and trust to potential customers. They may perceive your product as being of high quality and popular among other buyers, increasing the likelihood of them making a purchase.

3️⃣ Increased Sales
Higher visibility and credibility translate into increased sales potential. When your product ranks at the top, it is more likely to attract organic traffic and conversions. More people seeing your product can result in more clicks, which can lead to more sales.

4️⃣ Competitive Advantage
The Amazon marketplace is highly competitive, with numerous sellers offering similar products. Achieving a top ranking can give you a competitive edge over other sellers in your category. It allows you to stand out from the competition and capture a larger share of the market. Customers often compare products and make purchasing decisions based on the search results, so being at the top increases your chances of being chosen over competitors.

5️⃣ Algorithmic Factors
Amazon's search algorithm considers various factors when determining search rankings, such as relevance, sales velocity, customer reviews, and conversion rates. Higher search rankings lead to more exposure and sales, which, in turn, can improve your product's overall performance in the algorithm. This creates a positive feedback loop, where higher rankings can lead to more sales, and more sales can lead to higher rankings.

What is the Top-of-Search Optimizer and When to Use it?

The Top-of-Search Optimizer (TOSO), refers to the practice of optimizing your advertising campaigns to appear prominently at the top of search engine results pages (SERPs).

With Perpetua, TOSO is the Optimization Objective that can be enabled via launching a Keyword Boost (KB) if you are a Pro or Enterprise user (find out more about our subscription here).

In Perpetua, keyword boosts are a feature used to prioritize and bring more attention to selected keywords in your Sponsored Product goals by launching them in a separate campaign with a dedicated target ACoS and budget. Please find out more about Keyword boosts from this other very helpful article.

🚨Note: TOSO can only be applied to Keyword Boosts with a single EXACT match keyword in it. The option to add more keywords will be greyed out.🚨

By selecting TOSO as the Optimization Objective within your Keyword Boost, you prioritize the optimization towards Top-of-Search placement, rather than Target ACOS. Perpetua will then launch a separate campaign that will isolate that single keyword (used to launch the KB), to reach Top-of-Search (TOS) placements, by using Stream data to track and predict the best CPC for TOS (as well as ROS).

Bids are updated once a day.

TOS bids are applied using a TOS multiplier default to 900%.

🚨Note: If you are not already subscribed to Stream, you will be the day after activating Top-of-Search Optimizer. The Optimization will start then. If otherwise, please reach out to our team. Find out more about Stream from our Perpetua Ad School lessons here.🚨

You can view the TOS multiplier and the bids by navigating through the Keyword Boost campaign > Targets Tab:

As explained above, the ToS Engine works by overriding keyword bids. The keyword bid override will show up in the activity stream as “Target Updated” by with the bid value rounded to 0 decimal places as shown in the screenshot below:

How to Enable Top-of-Search Optimization?

Enabling this feature is only a few steps away:

  1. When setting up your Keyword Boost (How to here), assign a name to the campaign:

  2. Go to the “Optimization Objective” section and select the “Maximize Top of Search” option:

  3. When TOSO is selected, enter the Daily Budget value.
    Perpetua suggests setting a budget that is twice your average daily spending for these keywords.

    🚨Note: You may expect your budget to run out quickly since the day of launching your KWB with Top-of-Search Optimizer enabled, as the bids might be high to reach Top-of-Search. Gain more control over the Max. bid, by entering the optional Max. Bid explained in step 4 below. However, you will never spend more than the assigned daily budget.🚨

    🚨Note: “Going Dark Mitigation” does not apply to Top-of-Search Optimizer. Going dark is a phenomenon that happens in the other KPI Prioritization (Target Acos). When the budget is very tight on the campaign, going dark scales back engine target ACOS and the bid is reduced for all keywords throughout the day to conserve the budget to last for the whole day.
    When TOSO is selected for your KWB, the engine will not apply the above, meaning that the bids will not vary to save on budget.🚨

    4. Enter a "Max Bid" (Optional).
    This ensures that your bids for the selected keyword never exceed the specified value. It's important to be mindful, though, that this approach might impact performance, particularly in highly competitive Top-of-Search placements. Keep this consideration in mind as you optimize your bidding strategy.

    5. Click on the purple "Boost Keywords" button to create your Keyword Boost campaign with the TOS Optimizer. It will be listed in the “Campaigns” tab inside the goal, and in the “Keyword Boosts” from your “Experiments” tab. 🎉

Best Practices

1️⃣ Use Exact Match Keyword
Using an EXACT match is the cleanest way we could optimize for the top of search. Using PHRASE and BROAD match types could lead to some wasted spend due to the larger bracket of search terms that it would cover.

2️⃣ Name your Campaign after your Keyword
Name your campaign based on the name of the actual keyword you are optimizing. This will highlight the campaign among the campaigns’ list within the goal it was launched from.

3️⃣ Strategy Assessment
Use TOSO if your strategy aims to increase your conversion rate (CVR). TOSO will increase your bids to reach the Top-of-Search placement, by leveraging Stream data. This could lead your brand to gain a better organic rank and Share of Voice (SOV) over time.


❓ When you have multiple ASINs in the goal where you launched the KWB with the TOS optimizer, do we aim for full TOS coverage ❓
For a given campaign, only a single ASIN gets selected to be shown if the keyword wins the bid. Hence for a selected campaign, we only target one slot which we can get with the minimum CPC.

Why is Amazon Marketing Stream data used if we are only optimizing the bid once a day ❓

Amazon Marketing Stream data is the only dataset that attributes advertising KPIs (clicks, conversions, spend, sales) to the keyword-asin-placement level. Using this dataset, it gives us insight into how much a keyword-asin pair is spending on Top of Search placement.

Article last updated February 2024. If you find this information to be out of date, please contact

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