Fill Rate


In the context of technology, the term Fill Rate often refers to the rate at which requests for content, such as advertisements, are fulfilled or filled. It can be described as the percentage of ad impressions that are successfully filled from the total ad requests made from a website or app. Therefore, a high fill rate indicates more ad placements are being utilized, potentially leading to higher revenue for the publisher.


The phonetics of “Fill Rate” are: /fɪl reɪt/

Key Takeaways


  1. Definition: Fill Rate is a supply chain metric that measures the ability of a company to fulfill customer orders. It’s the fraction of customer demand that is met through immediate stock availability, without backorders or lost sales.
  2. Importance: Having a high Fill Rate means the business is efficiently meeting customer demand, while a low Fill Rate indicates problems with inventory management, which can lead to customer dissatisfaction and lost revenue.
  3. Calculation: Fill Rate is usually calculated as the total number of units delivered divided by the total number of units ordered by the customers. It is often expressed as a percentage.



Fill rate is a critical term in technology, particularly in the digital advertising and supply chain management industries. In digital advertising, fill rate refers to the percentage of ad requests that get filled with ads. A higher fill rate typically means more revenue for the publisher. In supply chain management, fill rate indicates the percentage of customer demand that is met through immediate stock availability, without backorders or lost sales. A higher fill rate in this context ensures customer satisfaction and efficiency in inventory management. Therefore, the fill rate not only reflects the efficiency or profitability of operations, but also the ability to meet customer or user needs, making it a significant benchmark in these industries.


The term “Fill Rate” is predominantly used in disciplines like digital marketing, supply chain management and technology, where it serves different yet important purposes. In the context of online advertising, a fill rate is a metric showing the percentage of ad inventory that is successfully filled with ads. Higher fill rates suggest more successful ad placements, which could potentially lead to increased revenue for publishers. It demonstrates the effectiveness of an ad server in finding suitable ads for the available ad space, which is critical for optimizing the profitability of a website or app.In supply chain management, fill rate refers to the measure of the ability of a process, system, or a company to meet customer demand for a product. It is often expressed as a percentage of the total order and signifies how much of customer’s order can be filled from the current inventory. A higher fill rate indicates that a company can meet customer demand more effectively, resulting in increased customer satisfaction and loyalty. Both these interpretations of fill rate are useful tools for assessing performance and profitability across different sectors.


1. E-commerce Industry: In the context of e-commerce and retail, fill rate refers to the percentage of customer orders that can be fulfilled from existing inventory. For example, if an online clothing store has 100 orders for a particular dress and they can immediately fulfill 70 of these from stock, they have a fill rate of 70%.2. Digital Advertising: In the world of digital advertising, fill rate refers to the number of ads served on a website or app relative to the number of opportunities available. For instance, if a website has 100 ad slots and 90 of them are successfully filled with ads, then the fill rate would be 90%.3. Warehousing and Logistics: In the context of warehousing, the fill rate might refer to the ratio of utilized space to the total available space in a warehouse. If a warehouse has the capacity to store 10,000 units and currently holds 7,000 units, then the fill rate is 70%.

Frequently Asked Questions(FAQ)

Q: What is Fill Rate?A: Fill Rate is a term often used in technology and online advertising to measure the percentage of delivered ads compared to the total number of ad requests. A higher fill rate indicates a greater proportion of ads successfully delivered.Q: Why is Fill Rate important?A: Fill Rate is an essential metric because it helps in evaluating the efficiency of an ad network or server. It also provides insight into the revenue generating potential of a website or app, as more ads filled means more earning opportunities.Q: How is Fill Rate calculated?A: Fill Rate is calculated by dividing the number of ads delivered or filled by the total number of ad requests, then multiplying the result by 100 to get a percentage. Q: What factors can affect Fill Rate?A: Several factors can affect Fill Rate, including the quality of the website or app, the relevance of the ads to the audience, the audience’s location, and the technical aspects like the ad server’s performance.Q: What is a good Fill Rate?A: A “good” Fill Rate can vary widely depending upon the context, like the type of ads, platform, and audience. However, generally anything over 80% is considered a good fill rate in online advertising.Q: Can I improve my Fill Rate?A: Yes, there are several strategies to improve Fill Rate such as optimizing your website or app, targeting relevant ads to your audience, and utilizing multiple ad networks or servers. Q: Is a 100% Fill Rate achievable?A: While it might seem ideal, a 100% Fill Rate is rare. It can often lead to showing low-quality or irrelevant ads, negatively impacting user experience and potentially reducing overall revenue.Q: If I have a low Fill Rate, does it mean my website or app is performing badly?A: Not necessarily. Low Fill Rate could mean that the ad requests are not being matched with relevant ads. It could also be due to technical issues. It’s important to identify the reason and work towards improving it. Q: Should I focus only on improving Fill Rate to increase my revenues?A: While improving Fill Rate can boost revenues, it shouldn’t be the only focus. Balancing Fill Rate with other factors like click-through rates, ad quality, and user experience is also essential. Q: What’s the difference between Fill Rate and Show Rate?A: Fill Rate refers to the number of ads delivered compared to the total number of ad requests, while Show Rate is the ratio of ads displayed to the total number of ads delivered. In other words, all ads included in the Show Rate are part of the Fill Rate, but not vice versa.

Related Finance Terms

  • Inventory Management
  • Stock Keeping Unit (SKU)
  • Order Fulfillment
  • Supply Chain Efficiency
  • Backorder Rate

Sources for More Information


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