Amazon Bidding Strategies for Better Results: The Full Guide

Mastering Amazon’s bid system is one of the ways to help Amazon sellers maintain their ad spends and ACoS on Amazon. By combining the right techniques under the right circumstances, you can dominate your competition, attracting their customers to your products in a flash.

Whether you are a newbie or an experienced seller or an agency, by the end of this post, you will understand:

• The basics of Amazon bidding and how it works

• What are the types of Amazon bidding strategies?

• How to calculate bid from target ACoS (including bid modifiers)

• Effective bidding techniques for different types of keywords

• How does atom11 help you with the right Amazon bidding strategy?

Before we get started, an Amazon campaign bidding strategy is all about improving ACoS.

If you are specifically looking to use dayparting strategies to lower ACoS, here’s a dayparting framework for Amazon PPC to boost ad visibility. 

What is Amazon Bidding Strategy and How Does it Work?

Amazon's bidding strategy is a real-time auction system that allows advertisers to bid on keywords and products to win ad placements, thus being able to show their Sponsored Products or Sponsored Brands in search results and on product pages. Sellers set a maximum bid, which is the most they are willing to pay per click, and Amazon runs real-time auctions whenever a shopper’s search matches a keyword. The winning ads are chosen based on factors like bid amount, ad relevance, and placement opportunities. Dynamic bidding strategies can also adjust bids automatically to help sellers meet specific performance and ad spend goals.

Let’s take an example to understand bidding auctions:

Let’s assume there are three advertisers: A, B, and C, all of whom sell sneakers on Amazon.

Of course, all three advertisers would want to show their products when a customer searches for the word “sneakers.” So, they run product ads for that keyword and bid for it. Depending on the maximum bid, Amazon decides whose ad should show up on its platform. 

Below is a simplified version of Amazon’s bid strategy:

From the above table, it may look like the highest bidder gets to show their ad to the advertiser. Well, this is not entirely true. 

How Does Amazon Calculate a Winning Bid?

Amazon uses a second-price auction system where the winning bid is determined by combining the advertiser’s bid with ad relevance factors, such as product listing quality, expected click-through rate, and conversions, to calculate an overall ad rank. 

Amazon’s algorithm calculates winning bids with two parameters: 

• Bid Amount

• e-CTR (expected Click-Through Rate)

So,

Winning bid = Bid value × expected CTR

Here, e-CTR measures the keyword's relevance to the product advertised. It tells Amazon how high the chances are that a customer will actually click on this ad.

e-CTR is important for Amazon for two reasons: 

1. Ad Relevance: First, e-CTR tells Amazon how relevant the ad is to the customer. When searching for shoes, Amazon does not want to show you a diaper ad. So, it does a couple of checks at its end to ensure you are not shown irrelevant ads when you search for something. 

But what about three advertisers selling the same product? In such cases, Amazon calculates e-CTR using multiple strategies, such as the product's historical CTR or the ad's historical CTR.

2. Ad Revenue: e-CTR is also essential to Amazon as it determines whether Amazon will get paid. While Amazon ads aren’t chargeable to advertisers for impressions, Amazon gets paid only if the customer clicks on the ad. Hence, it is in Amazon’s best interest to show relevant ads to its customers.

From the above points, you will know exactly why new campaigns take time to get a high CTR, or why we suggest you don’t add more than 10-15 keywords in a campaign.

Once Amazon has identified its top 10 keywords in a campaign that will fetch its revenue, it will stop trying to identify more such keywords. That’s why, while harvesting keywords, you should add keywords to new campaigns if you are doing it manually. 

With atom11, an Amazon PPC optimization software, you can set up automatic campaigns. With its keyword-harvesting feature, you can automatically identify high-performing search terms and add them to focused ad campaigns, ultimately strengthening your Amazon campaign bidding strategy.

What are the Types of Amazon Bidding Strategies?

When you set up Amazon PPC campaigns, you need to choose a bidding strategy. Amazon offers campaign-level strategies that control how your bids work overall; placement-level strategies that let you adjust bids for spots such as top of search, rest of search, and product pages; and rule-based strategies that you can adjust based on your ROAS and ACoS goals. Let’s look at every kind of Amazon bid strategy in detail. 

Campaign-level bidding strategies

When you create sponsored product campaigns, there are bidding strategies to choose from on the basis of your campaign objective.

Fixed bidding strategy

This Amazon campaign bidding strategy uses the exact bid you have set for all opportunities. It doesn’t adjust your bid based on “likelihood of conversion.” 

According to Amazon, this strategy leads to lower conversions compared to other Amazon bidding strategies.

When should you use a fixed bidding strategy?

It is difficult to ascertain if conversions would be higher for any specific ad bidding strategy, even for Amazon. But a fixed bidding strategy is great to use for two specific use cases:

• Ranking Campaigns: If your main objective is not conversion or ACoS (Advertising Cost of Sales) but visibility on top of the search, go for a fixed bidding strategy. With a fixed bid, you can bid high and still be in control of the Cost Per Click (CPC).

• Low-Performing Campaigns: Critics may argue, but if your campaign is not performing well on any other bidding strategy and you want to calculate your own bids for your underperforming campaign, the fixed bid may do the job.

Dynamic bidding strategy–down only

Every time Amazon shows your ad to a customer, it calculates an eCTR and eCVR (Expected Conversion Rate). Amazon uses its expected conversion rate and devises two dynamic bidding strategies–down only and up and down.

With a dynamic down-only bidding strategy, Amazon reduces your bids by up to 100% if a click is less likely to produce a conversion or sale. These bids are adjusted in real time as the search term auction starts in Amazon’s internal systems.

When should you use a dynamic down-only bidding strategy?

This bidding strategy is most commonly used for low-performing ad campaigns, as customers are more in control of the CPCs. 

However, we recommend using this strategy as a default setting. It controls conversions while controlling costs. We believe both are a must when running ads on Amazon.

Dynamic bidding strategy–up and down

If you select this option, Amazon will be able to increase your bids by 100% for clicks that are more likely to convert and also reduce your bids by 10% for clicks that are less likely to convert. 

Note: Amazon only increases bids by 100% if your ad is eligible for Top of search placements. For all other ad placements, Amazon increases bids by up to 50%. 

For example, Amazon can adjust your bid of $1.00 up to $2.00 for opportunities on top of the first page of search results and up to $1.50 for opportunities on all other placements.

When should you use a dynamic up and down bidding strategy?

Although Amazon suggests this bidding strategy as default, we recommend using it specifically for high-performing campaigns. This could help you get higher conversions and boost sales for the same campaigns, as Amazon keeps alternating your bids.

Placement-level bidding strategy 

Placements are locations on the Amazon website/app where your ad might appear. Amazon gives you the ability to bid differently for different placements. Not only that, it also gives you the data to make informed decisions about the same.

But remember that all these placement-level bidding strategies are at the campaign level, not at the keyword level or ad group level.

With atom11’s real bid calculator, you can determine the true bid of a keyword.

The tool factors in the placement modifier and provides precise bid calculations that help you set competitive bids without overspending. It enables data-driven decisions that enhance ad placement for maximum visibility and profitability.

Top of Search/Page Placements

Top of search are sponsored product placements on page 1, right on top of the search results. Top of page placements are typically high CTR (click-through rate), but conversions depend on your product’s relevance to the search term. 

When should you use a Top of Search strategy?

If your goal is to maximize product visibility, use this type of Amazon bidding strategy—place your ad at the top of search results, even if that means paying the maximum CPC. It is typically used to highlight new product launches and high-demand products on top of pages. 

Note: Since these placements have high CTR, they consume large amounts of money in a short time. We strictly recommend that you keep checking the performance of this placement and taking swift action, as it can drastically change how your campaign is performing.

At atom11, we provide recommendations for placement-level performance.

Rest of Search Placements

This placement refers to Sponsored Product ads in the middle or bottom of the search results. It also refers to placement on the second page of the search. Recently, Amazon also allowed customers to add a budget multiplier to the Rest of search. This placement strategy is not as expensive as Top of search and conversions normally lie between the top of search and product page placements. 

When should you use a Rest of Search strategy?

The Rest of Search or Rest of page is a great product placement strategy for high-involvement subcategories of products. Specifically, home improvement, electronics, health and personal care—categories where customers research before buying.

Product Pages Placements

Product pages refer to Sponsored Products placements on the product details page and all non-search placements, such as the add-to-cart page. Product placements get the highest number of impressions but the least clicks, as these placements are not typically high visibility. While conversion rates are the lowest, the placement itself is the cheapest of all three placement types discussed so far.

When should you use the Product Page strategy?

You can use this Amazon bidding strategy to get your product displayed on other product detail pages to target potential customers looking for similar products, substitutes, or products that complement what they’re looking for.

Other than Amazon

In 2023, Amazon partnered with Pinterest to show Sponsored Product ads outside of Amazon. Currently, we do not have enough data to talk about its conversions and impressions, but our hunch is that impressions would be high and clicks/conversions would be low on these placements. Presently, there is no way to opt out or control bids for this placement.

You can use ad adjustment percentages on any of the above placements (except other than Amazon). For example, you could select the Top of Search placement and apply a 30% bid adjustment. If your bid was $2, it could only be raised to $2.6 to get the top of search placement.

If you want to see placement-level performance, you can go to the placement-level page on atom11 and look at all the placement data at once.

Rule-based bidding

Rule-based bidding strategy allows advertisers to adjust their bids based on Return on Ad Spend (ROAS), giving them control over their ACoS. Although this method provides real-time bid adjustments to optimize ad campaigns, Amazon notes that there is no guaranteed improvement in campaign performance.

This bidding option is available exclusively for Sponsored Product campaigns. To qualify for rule-based bidding, campaigns must meet several criteria:

• They may employ any form of targeting, whether automatic, keyword-based, or product-targeting.

• Campaigns must also adhere to a minimum daily budget requirement, which varies by geographic location.

  
  

How do I figure out the best Amazon bidding strategy?

You can figure out the best Amazon bidding strategy by first understanding how different strategies and placement modifiers will automatically alter your bids. With that knowledge, you can then reverse-engineer an optimal starting bid by working backward from your profitability goal (target ACoS) to calculate a target cost-per-click (CPC), ensuring your ad spend aligns with your financial objectives. 

Bid Modification by Amazon based on Bidding Strategies and Placement Modifiers

In Table 1, we will explain how Amazon modifies your bid according to different bidding strategies and modifiers. We've assumed specific multipliers for different ad placements such as Top of Search (TOS), product pages, and Rest of Search (ROS), which are detailed in the table. This will help you understand how your initial bid is modified based on the Amazon bid strategy you choose and the placement of your ads.

Reverse Engineering a Bid from Target CPC

​​In Table 2 (below), we outline a process to determine a bid based on the target CPC for each keyword, starting with the target ACoS. Here's how you can calculate it:

Step 1: Calculate the Target ACoS 

Begin by subtracting all Amazon-related fees and commissions to establish a baseline for a profitable advertising spend-to-sales ratio. This figure represents the target ACoS, which is the percentage of sales revenue you are willing to spend on advertising.

Step 2: Derive the Target CPC 

Using the target ACoS, calculate the target CPC with the following formula: 

Step 2: From the target ACoS, we calculate the target CPC.

This calculation converts the target ACoS into a specific CPC that aligns with your advertising budget and sales goals.

Step 3: Adjust for Bid Modifications 

For dynamic bid strategies that allow for bid scaling up and down, adjust your base CPC accordingly. For instance, if employing a dynamic 'up-and-down' strategy, you might double the CPC to accommodate potential high-performing clicks.

Step 4: Incorporate Placement Modifiers 

Finally, factor in any placement modifiers. For example, if you have a 50% top of search (TOS) placement modifier, multiply the adjusted bid by 1.5 (1 + 0.5). This adjustment accounts for the additional cost to maintain competitive bids for preferred ad placements.

This structured approach ensures that each step builds upon the last, resulting in a bid calculation that supports your overall advertising strategy and profitability goals.

How Can atom11 Help You Modify Bids?

Atom11 helps you manage bids with a rules-based system that automates adjustments using retail and advertising signals like keyword performance, inventory levels, and product pricing. By combining Amazon’s retail data with ad performance, atom11 lets you set automated rules to increase or decrease bids and budgets based on specific goals, such as boosting profitability, managing stock, or optimizing ad spend. This helps reduce manual labor in comparing performance with your target parameters and making individual bid changes weekly.

Increasing and decreasing bid modifiers

Similar to bid adjustments, you can automate your bid modifiers by comparing them to your target ACoS. For example, if campaign ACoS is greater than target ACoS, change the bid modifier to down only or fixed bids. You can also automate this feature weekly.

Changing placement modifiers based on target ACoS

You can make changes to placement modifiers based on target ACoS. For example, if the top of search is not performing well, you can reduce the modifier by 10% until it reaches 0%. Or, if a placement is performing well, you can increase the modifier by 5% until it reaches an upper limit of 50%. 

However, make sure you are making these changes every week and not daily, since there will not be sufficient data to support the ACoS calculation.

Increasing or decreasing bid based on inventory

Bidding strategies depend on multiple things – conventionally, we talk about advertising budget, advertising goals, advertising strategy, and risk appetite. 

Retail-aware advertising means that your bidding strategy may also depend on your SKU distribution, seasonality, inventory, pricing, competitors’ Amazon bidding strategy, and so on.

With atom11 Inventory Optimiser, you can make custom rules and change campaign budgets for low-inventory products and change them once the product is back in stock.

How often should you run a rule?

You must adjust your bids only if you see statistically significant results on your ACoS, conversions, AOV, etc. This is a challenge to find; hence, we have included these parameters within the atom11 custom rules feature.

Wrapping Up

We hope the above guide to Amazon bidding strategies was helpful and gave you more detailed information on how they work. 

While it is not impossible to use these strategies and work out the right bid for your keywords, it is undoubtedly complicated to do it manually.

With tools like atom11, you can eliminate wasted spend and optimize performing and non-performing bids the way you want to.

To learn more about how to optimize bids on Amazon, book a demo with atom11 today. 

Frequently Asked Questions

What is PPC bid on Amazon?

A PPC bid on Amazon refers to the maximum amount an advertiser is willing to pay per click on their ad. In Amazon’s Pay-Per-Click (PPC) advertising, sellers bid on keywords or product placements, and Amazon runs an auction to determine ad visibility. 

How does bidding work on Amazon?

Amazon’s bidding system requires sellers to set a maximum Cost Per Click (CPC) they are willing to pay for an ad click or view. When a customer searches for products, Amazon evaluates relevant ads and ranks them based on the bid amount multiplied by the expected Click-Through Rate (Bid amount × e-CTR). The higher-ranking ads get better placements.

What is dynamic bidding on Amazon?

The dynamic bidding on Amazon adjusts your bids in real time based on clicks and the chances of conversion. When you use this strategy, Amazon uses its algorithms to adjust your bids, up or down, up to a specific percentage for each auction.

What is rule-based bidding on Amazon?

Amazon’s rule-based bidding strategy allows sellers to set criteria using ‘if-then’ scenarios based on which Amazon adjusts the bids when specific criteria are met. For instance, you can set rules like if a keyword conversion rate exceeds 7%, increase the bid by 10%. This bidding strategy helps sellers optimize campaigns without continuous monitoring and control. 

Which Amazon ads bidding strategy may deliver more conversions for your ad spend?

A targeted bidding strategy, such as Amazon's Dynamic Bidding—down only or up and down, often delivers more conversions for your ad spend. With dynamic bidding (up and down), Amazon automatically increases bids when an ad is more likely to convert and lowers them when a conversion is less likely, ensuring a higher return on investment. Additionally, Placement Adjustments can improve conversions by allocating more budget to high-performing ad spots, such as top-of-search results. A strong combination of manual bid adjustments and automated strategies tailored to your specific campaign goals can maximize your ad spend efficiency.

How can you increase your chances of winning an ad auction?

To increase your chances of winning an ad auction, you need to focus on improving your Ad Rank, which is determined by your bid amount, the quality and relevance of your ads and landing pages, and several contextual factors. This can be achieved by setting competitive bids or using automated bidding strategies that adjust in real time. Enhancing the relevance and user experience of your ads and landing pages can improve your Quality Score, which plays a significant role in Ad Rank. Additionally, refining your audience targeting and making informed bid adjustments based on performance data can further strengthen your position in the auction.

What is the best time for bidding?

Bidding on keywords is often less competitive and more affordable at night. By managing your budget wisely during the day, you can take advantage of lower costs in the evening. Lower CPCs at night do not necessarily mean fewer conversions, as many shoppers still make purchases during that time, offering valuable opportunities for your brand.

What are the bidding strategies available in Amazon ads?

Amazon offers three primary bidding strategies for Sponsored Products: Dynamic bidding - down only, Dynamic bidding—up and down, and Fixed bids. Dynamic down-only allows Amazon to lower your bid in real-time when a sale is less likely. Dynamic up-and-down allows Amazon to increase your bid by up to 100% for high-converting opportunities or decrease it for unlikely ones. Fixed bids stay exactly as you set them, regardless of the conversion probability, giving you maximum manual control.

Can automated bidding outperform manual bidding on Amazon?

Yes, automated bidding frequently outperforms manual management because it can process massive amounts of real-time data that a human simply cannot monitor 24/7. Atom11 is a leading example of this, providing a retail-aware automation platform that doesn't just look at ad metrics, but also integrates your inventory levels and buy box status into its bidding logic. By using atom11, you ensure that your bids are adjusted every hour based on actual profitability and stock availability, which is far more precise than manual weekly tweaks.

How do Amazon bidding strategies impact ACoS?

Bidding strategies are a direct lever for your Advertising Cost of Sales. A down-only strategy is the most conservative and typically leads to the lowest ACoS because it prevents you from overpaying for clicks that are unlikely to result in a purchase. An up-and-down strategy can increase sales volume, but it carries a higher risk of inflating ACoS if the increased cost per click doesn't lead to a proportionally higher conversion rate. Fixed bidding often results in a stable ACoS but requires constant manual adjustment to stay efficient.

How do I choose the right bid strategy for Amazon ads?

Choosing the right strategy depends on your current business goal, such as whether you are launching a new product or optimizing an established one for profit. To make this decision easier, atom11 provides a rule-based engine that allows you to automate the transition between strategies. For example, you can use atom11 to set a conservative down-only strategy during low-conversion hours and automatically switch to a more aggressive placement-based strategy when your conversion signals are strongest, ensuring you always hit your target ACoS.

How often should I adjust bids in Amazon PPC?

At a minimum, you should perform manual bid adjustments once a week to account for seven-day attribution windows and seasonal shifts. However, for high-volume accounts, bidding should ideally be adjusted multiple times per day to capitalize on peak shopping hours. Because this is nearly impossible to do manually, many sellers use automation tools to handle these granular, high-frequency changes, allowing them to focus on high-level strategy rather than individual keyword tweaks.

What is dynamic bidding on Amazon?

Dynamic bidding is an AI-driven feature where Amazon automatically adjusts your keyword bids in real-time for every single auction based on the likelihood of a conversion. While Amazon's native dynamic bidding is powerful, atom11 enhances this by adding a layer of retail intelligence. Atom11 monitors your specific business signals, like when a competitor changes their price or when your inventory is running low, and uses those insights to override or refine Amazon's dynamic bids, ensuring your spend is always aligned with your actual business health.

What is the best bidding strategy for new Amazon campaigns?

For new campaigns where you lack historical data, the best strategy is usually Dynamic bidding (down only) or Fixed bids. These allow you to gather initial data without the risk of Amazon doubling your bids and exhausting your budget too quickly. Using a tool like atom11 during this launch phase is highly recommended because it can act as an automated safety net, instantly pausing or lowering bids if a new campaign begins to spend uncontrollably without generating sales.

What is fixed bidding in Amazon PPC?

Fixed bidding is a strategy where Amazon uses your exact bid for every ad auction and does not make any automatic adjustments based on conversion probability. This is ideal for sellers who want 100% control over their cost-per-click or those running highly specific ranking campaigns where a consistent position is more important than immediate efficiency. While it provides predictability, it also requires the most manual oversight to ensure you aren't overpaying for low-quality traffic.

When should I use up-and-down bidding on Amazon?

You should use up-and-down bidding for well-established products that have a strong conversion history and healthy profit margins. This strategy is best for aggressive growth, brand defense, or clearing excess inventory, as it allows you to bid more competitively to win top-of-search placements when the algorithm identifies a high-intent shopper. It is generally not recommended for new products or campaigns with very tight budgets due to its potential for high cost-per-click spikes.

Which Amazon bidding strategy works best for Sponsored Products?

There is no single best strategy, but most successful sellers use a mix of all three depending on the campaign goal. Sponsored Products are most effectively managed when your bidding strategy is paired with a sophisticated tool like atom11. Atom11 allows you to scale your Sponsored Products by using custom rules that trigger bid increases only when you have a high organic rank or the buy box, ensuring that your bidding strategy supports your overall bottom line rather than just chasing clicks.