Email Campaign Performance Metrics Definitions

Overview

Everyday Email marketers face difficult decisions trying to compare and purchase Email-related services. In fact, a recent study by the Email Experience Council highlighted the lack of standardization around Email definitions and metrics and found that inconsistency in these areas makes it difficult for marketers to manage and improve upon their campaigns and/or e-newsletters.

The IAB Email Committee is taking an evolutionary approach. First, this document was created to guide marketers and vendors towards more consistency in what the current Email terminology actually describes. Once more consensus has been achieved in this area, we can then, as an industry, start to look at places to encourage standardization and/or improvement of the methodologies behind these metrics, for example, standardizing the way ISP bounce codes are delivered. Overall, change is an industry effort and we look forward to working with other associations in improving upon campaign performance evaluation tools.

As a marketer or vendor, you may use or have access to some of these metrics, but not others depending on your software and/or service provider. Please note that some functionality may be available as a third-party add-on to other services. The Proposed Terms below represent the metric as a “snapshot” of, or at a "moment in time” within, a particular campaign.


Basic Definitions

These words and phrased are used throughout the Proposed Terms below and, as such, it may be helpful to refer to them prior to or during further review.

Bounce: An Email that cannot be delivered to the mailbox provider and is sent back to the Email Service Provider that sent it. A bounce is classified as either “hard” or “soft.” Hard bounces are the failed delivery of Email due to a permanent reason, such as a non-existent address. Soft bounces are the failed delivery of Email due to a temporary issue, such as a full inbox or an unavailable ISP server.

Email Service Provider (ESP): A business or organization that provides the Email campaign delivery technology. ESPs may also provide services for marketing, advertising and general communication purposes.

Inbox: Within a mailbox provider, the default, primary folder that stores delivered Email messages.

ISP: A business or organization that providers internet access, and related services, to consumers.

"Junk" or "Bulk" Email Folder: An inbox-alternative folder, within a mailbox provider, that stores Email messages that are, for various reasons or rationale, unable to be delivered to the inbox.

Mailbox Provider: The Email program, and by extension the server, that hosts the targeted Email address.

Preview Pane: A small window within a mailbox provider that allows the user to view some Email content without opening the Email.


Email Campaign Performance Metrics

Actual Performance of an Email Campaign

Email Conversions
Although not all Email messages are intended to drive a purchase, most messages have some “call to action,” such as a click-through or confirmation. If these kinds of conversions are an applicable metric of success, then this metric attempts to answer the question, “How many registrations, purchases, or other actions were taken as a direct result of this Email campaign?” This metric is a whole number in the form "100,000" or as an Email Conversion Rate percentage in the form "5%". The denominator is Email Delivered.

Email Revenue
This metric attempts to answer the question, “How much revenue was generated either as a direct result of this Email campaign, or, if Email is part of a multi-channel campaign, as a function of an advertiser-assigned value?” This metric is a monetary amount in the form "$20,000.00" or as CPM in the form "$20 CPM".

Email Gross Profit
This metric attempts to answer the question, "How much revenue was generated as a direct result of this Email campaign, minus any direct costs, such as the cost of deployment, the cost of creative development, the cost of list rental, unsubscribes/lost opportunity, complaints, customer service, etc."

Effective Email Cost-per-Thousand (Email eCPM)
This metric is typically used for list rental and attempts to answer the question, “How much revenue was generated per email impressions delivered? It may be calculated by subtracting costs associated with sending the Emails from revenue generated, then dividing by the number of impressions delivered, and finally multiplying that number by 1000.


Indicators of Activity Generated By a Campaign

Total Email Opens
This metric attempts to answer the question, "How many times did a person look at the Email campaign?" In practice, recording of user activity is a way to confirm that the recipient viewed the message. Loading of an invisible pixel is generally sufficient to qualify as an Open. This metric is a whole number in the form "100,000" or as an Email Open Rate percentage in the form "25%". The denominator is Email Delivered.

NOTE: Some Opens may not be detected when, for example, the user has images disabled, is on a mobile device, or has elected to receive text-only Emails. The metric may also falsely indicate some impressions when the message is briefly loaded into the Preview Pane but may not be actually viewed by the recipient.

Unique Email Opens
This metric is similar to an Email Open, but here, duplicate opens are eliminated. This attempts to answer the question, "How many unique individuals viewed this Email campaign?" This metric is a whole number in the form "100,000" or as a Unique Email Open Rate percentage in the form "25%". The denominator is Email Delivered.

Total Email Click-Throughs
This metric attempts to answer the question, "How many times did a person click on a link or multiple links within this Email?" This may or may not include clicks on unsubscribe links or other links and you may find it helpful to view click-through reporting by individual link. This metric is a whole number in the form "100,000" or as an Email Click-through Rate percentage in the form "10%". The denominator is Email Delivered and this percentage may exceed 100%.

Unique Email Click-Through
This metric attempts to answer the question, "How many unique people clicked on a link or multiple links within this Email?" To illustrate, if one person clicked on two links, this would only count as one unique click-through. If one person clicked on the same link twice, this would only count as one unique click-through. This metric is a whole number in the form "100,000" or as a Unique Email Click-through Rate percentage in the form "10%". The denominator is Email Delivered.

Click-to-Open Rate
This metric attempts to answer the question, “Of the Unique Email Opens, how many individuals took an action?” This metric is a percentage in the form of “30%.” It is generally calculated as either Unique Click-Throughs over Unique Email Opens; or Total Email Click-Throughs over Total Email Opens.

Email Forwards
This metric attempts to answer the question, "How many times was this message forwarded from the original recipient to a new recipient?" Forwards can be calculated using a number of different methods. This metric is a whole number in the form "10,000" or as an Email Forward Rate percentage in the form "0.1%". The denominator is Email Delivered.


Overall Deliverability Metrics of A Campaign

Used in combination, the metrics “Email Sent”, “Email Delivered” and “Email Inbox Delivered” can provide some insight into the overall deliverability rates of a campaign.

Email Sent
This metric attempts to answer the question, "How many did you try to send?" In other words, it describes how many messages were in the queue before any delivery attempts were made, but after any necessary internal suppression has been performed. This metric is commonly used to bill for Email Service Provider delivery, but not for third party list rental. This metric is a whole number in the form "100,124".

Email Delivered
This metric attempts to answer the question, "How many valid Email addresses actually accepted my complete message?" In other words, it describes how many were completely transferred to the intended recipient’s mailbox provider without generating a “bounce” or other delivery error. This metric is calculated before the impact of content-based filtering is factored in. If a message is rejected by the mailbox provider, it does not count as delivered. However, if the message is accepted and placed in a “junk Email” folder it generally does count as delivered. This is currently the most common metric used to purchase Email advertising by CPM or third party list rental. This metric is a whole number in the form "100,032" or as an Email Delivery Rate percentage in the form "95%" and the inverse of this number is known as the "bounce rate." The denominator is Email Sent.

Email Inbox Delivered
This metric attempts to answer the question, "How successful was this Email campaign at being delivered to the inbox?" This number is usually generated using an estimation based on delivery to special seed accounts. The metric is generally calculated by taking the metric Email Delivered and subtracting any messages that do not appear in the Inbox. This metric is a whole number in the form "99,234" or as a percentage in the form "90%" with the denominator as Email Delivered.


Branding, Impact on Long-Term Deliverability, and Compliance

The terms below only consider actions taken through a delivered Email. Logging Email Unsubscribe Requests or Email Complaints may also be done through channels such as postal mail, online forms in a preference center and “Customer Call Centers” and may be factored into the metrics for a particular campaign at a later time. Reported Email Unsubscribe Requests may or may not include Email Complaints.

Email Unsubscribe Requests
This metric attempts to answer the question, "How many people unsubscribed from this Email campaign as a direct result of an action taken via a delivered Email?" This metric is a whole number in the form "10,000" or as an Email Unsubscribe Rate in the form percentage "0.1%". The denominator is Email Delivered.

Email Complaints
This metric attempts to answer the question, “How many people actively clicked a link in their Email software to Report [this as] “Spam” or Report [this as] “Junk”?” If they are available, and in order receive this information, you will likely need to sign up for feedback loops from individual ISPs. This metric is a whole number in the form "1,000" or as an Email Complaint Rate in the form percentage "0.01%". The denominator is Email Delivered.