In product development, teams often rely on a handful of familiar metrics to judge success. Retention rates, click-through rates, or conversion percentages frequently become the primary signals guiding product decisions. While these metrics can be useful, they rarely capture the full picture of how people actually experience a product.
This is where the HEART framework offers a more human-centred approach to measurement.
Developed at Google by UX researchers Kerry Rodden, Hillary Hutchinson and Xin Fu, the HEART framework was introduced in the paper “Measuring the User Experience on a Large Scale: User-Centered Metrics for Web Applications.” (Link to paper here) It was presented at the CHI Conference on Human Factors in Computing Systems and has since become one of the most widely used models for measuring user experience in digital products.
The framework helps teams connect product metrics with actual user experience, rather than focusing purely on behavioural numbers.
What HEART stands for
HEART is an acronym representing five categories of user-centred metrics:
• Happiness
• Engagement
• Adoption
• Retention
• Task Success
Each category represents a different aspect of how users experience a product. Together they provide a more complete picture than traditional product metrics alone.
Happiness
Happiness measures how satisfied users feel when interacting with a product.
This is typically captured through:
- satisfaction surveys
- user feedback
- Net Promoter Score (NPS)
- usability ratings
Rather than asking only what users do, this metric asks how they feel about doing it.
Engagement
Engagement measures how actively users interact with the product.
Typical indicators include:
- frequency of use
- session depth
- feature interaction
- time spent in meaningful workflows
Engagement focuses on whether users find the product valuable enough to repeatedly interact with it.
Adoption
Adoption measures how many new users start using a product or feature.
For example:
- number of first-time users
- percentage of users who try a new feature
- sign-ups for a newly launched capability
Adoption helps teams understand whether new functionality is successfully entering the user’s workflow.
Retention
Retention measures whether users return over time.
Examples include:
- returning weekly users
- percentage of users active after 30 days
- churn rates
Retention is often already measured in many organisations, but within HEART it becomes one component of a broader experience model rather than the single definition of success.
Task Success
Task Success measures how effectively users can complete their intended goals.
Common indicators include:
- task completion rate
- time to complete a task
- error rate
- number of steps required
This category focuses directly on usability and efficiency, making it particularly valuable when designing complex tools or workflows.
Do you need to use all five HEART metrics?
One of the strengths of the HEART framework is its flexibility. It is not always necessary to measure all five categories at the same time.
In practice, teams often select two or three metrics that best reflect the goal of a specific project or feature.
For example:
• A new feature launch may focus primarily on Adoption and Engagement
• A workflow redesign may prioritise Task Success and Happiness
• A subscription product may emphasise Retention and Engagement
Using all five categories can provide a comprehensive view of the user experience, but it is often more practical to focus on the metrics that are most relevant to the problem you are trying to solve.
The key idea behind HEART is not to track more metrics, but to ensure that at least some of them reflect the quality of the user experience, not just behavioural activity.
How the HEART framework is used in practice
The strength of HEART lies in how it translates abstract user experience goals into measurable signals.
Example 1: Improving a checkout experience
A team redesigning an e-commerce checkout flow might measure:
- Happiness: post-purchase satisfaction survey
- Engagement: number of interactions with saved payment methods
- Adoption: percentage of users trying the new checkout flow
- Retention: users returning to purchase again
- Task Success: checkout completion rate and time to complete payment
This allows the team to understand whether improvements actually make the experience easier and more satisfying, not just whether users clicked a button.
Example 2: Designing tools for financial decision-making
In financial software, users often work with complex data, high stakes decisions and fragmented workflows.
A product designed for credit assessors, for instance, might track:
- Happiness: perceived confidence in risk decisions
- Engagement: how often the interface is used for case reviews
- Adoption: percentage of assessors switching to the new interface
- Retention: continued usage over several months
- Task Success: time required to evaluate a credit case
In environments where accuracy and trust are essential, task success and confidence often matter more than raw click metrics.
Why HEART is better than relying on single metrics
Many product teams rely heavily on simple indicators such as click-through rate or retention. While useful, these metrics can be misleading when interpreted in isolation.
A high click rate does not necessarily mean users understand a product.
A high retention rate does not guarantee the experience is enjoyable.
Users may return simply because they have no alternative, not because the product serves them well.
The HEART framework improves measurement in three important ways.
1. It balances behaviour and perception
Traditional analytics measure behaviour. HEART combines behaviour with user sentiment and satisfaction, giving a more complete view of experience quality.
2. It focuses on user goals
Rather than optimising superficial metrics, HEART encourages teams to measure whether users successfully achieve their intended tasks.
3. It aligns teams around experience outcomes
Because HEART connects metrics to experience categories, it becomes easier for designers, product managers and engineers to discuss what success actually means for users.
Measuring what matters
In complex digital products, especially those involving decision-making, analysis or professional workflows, success cannot be reduced to a single number.
The HEART framework reminds us that a good product is not simply one that is used frequently. It is one that users understand, trust and succeed with.
By combining satisfaction, engagement, adoption, retention and task success, teams can move beyond surface-level metrics and begin measuring something far more meaningful:
the quality of the user experience itself.
The HEART Framework: Measuring What Truly Matters in Product Design
In product development, teams often rely on a handful of familiar metrics to judge success. Retention rates, click-through rates, or conversion percentages frequently become the primary signals guiding product decisions. While these metrics can be useful, they rarely capture the full picture of how people actually experience a product.
This is where the HEART framework offers a more human-centred approach to measurement.
Developed at Google by UX researchers Kerry Rodden, Hillary Hutchinson and Xin Fu, the HEART framework was introduced in the paper “Measuring the User Experience on a Large Scale: User-Centered Metrics for Web Applications.” It was presented at the CHI Conference on Human Factors in Computing Systems and has since become one of the most widely used models for measuring user experience in digital products.
The framework helps teams connect product metrics with actual user experience, rather than focusing purely on behavioural numbers.
What HEART stands for
HEART is an acronym representing five categories of user-centred metrics:
• Happiness
• Engagement
• Adoption
• Retention
• Task Success
Each category represents a different aspect of how users experience a product. Together they provide a more complete picture than traditional product metrics alone.
Happiness
Happiness measures how satisfied users feel when interacting with a product.
This is typically captured through:
- satisfaction surveys
- user feedback
- Net Promoter Score (NPS)
- usability ratings
Rather than asking only what users do, this metric asks how they feel about doing it.
Engagement
Engagement measures how actively users interact with the product.
Typical indicators include:
- frequency of use
- session depth
- feature interaction
- time spent in meaningful workflows
Engagement focuses on whether users find the product valuable enough to repeatedly interact with it.
Adoption
Adoption measures how many new users start using a product or feature.
For example:
- number of first-time users
- percentage of users who try a new feature
- sign-ups for a newly launched capability
Adoption helps teams understand whether new functionality is successfully entering the user’s workflow.
Retention
Retention measures whether users return over time.
Examples include:
- returning weekly users
- percentage of users active after 30 days
- churn rates
Retention is often already measured in many organisations, but within HEART it becomes one component of a broader experience model rather than the single definition of success.
Task Success
Task Success measures how effectively users can complete their intended goals.
Common indicators include:
- task completion rate
- time to complete a task
- error rate
- number of steps required
This category focuses directly on usability and efficiency, making it particularly valuable when designing complex tools or workflows.
Do you need to use all five HEART metrics?
One of the strengths of the HEART framework is its flexibility. It is not always necessary to measure all five categories at the same time.
In practice, teams often select two or three metrics that best reflect the goal of a specific project or feature.
For example:
• A new feature launch may focus primarily on Adoption and Engagement
• A workflow redesign may prioritise Task Success and Happiness
• A subscription product may emphasise Retention and Engagement
Using all five categories can provide a comprehensive view of the user experience, but it is often more practical to focus on the metrics that are most relevant to the problem you are trying to solve.
The key idea behind HEART is not to track more metrics, but to ensure that at least some of them reflect the quality of the user experience, not just behavioural activity.
How the HEART framework is used in practice
The strength of HEART lies in how it translates abstract user experience goals into measurable signals.
Example: Improving a checkout experience
A team redesigning an e-commerce checkout flow might measure:
- Happiness: post-purchase satisfaction survey
- Engagement: number of interactions with saved payment methods
- Adoption: percentage of users trying the new checkout flow
- Retention: users returning to purchase again
- Task Success: checkout completion rate and time to complete payment
This allows the team to understand whether improvements actually make the experience easier and more satisfying, not just whether users clicked a button.
Why HEART is better than relying on single metrics
Many product teams rely heavily on simple indicators such as click-through rate or retention. While useful, these metrics can be misleading when interpreted in isolation.
A high click rate does not necessarily mean users understand a product.
A high retention rate does not guarantee the experience is enjoyable.
Users may return simply because they have no alternative, not because the product serves them well.
The HEART framework improves measurement in three important ways.
1. It balances behaviour and perception
Traditional analytics measure behaviour. HEART combines behaviour with user sentiment and satisfaction, giving a more complete view of experience quality.
2. It focuses on user goals
Rather than optimising superficial metrics, HEART encourages teams to measure whether users successfully achieve their intended tasks.
3. It aligns teams around experience outcomes
Because HEART connects metrics to experience categories, it becomes easier for designers, product managers and engineers to discuss what success actually means for users.
Measuring what matters
In complex digital products, especially those involving decision-making, analysis or professional workflows, success cannot be reduced to a single number.
The HEART framework reminds us that a good product is not simply one that is used frequently. It is one that users understand, trust and succeed with.
By combining satisfaction, engagement, adoption, retention and task success, teams can move beyond surface-level metrics and begin measuring something far more meaningful:
the quality of the user experience itself.
