Digital marketing KPIs are measurable metrics that indicate how effectively your campaigns achieve business goals. They guide decision-making, optimise performance, and ensure measurable growth.

Key KPIs include website traffic, conversion rate, customer acquisition cost (CAC), return on ad spend (ROAS), engagement rate, and customer lifetime value (CLV). Each metric provides insights into different aspects of performance.

Use analytics tools like Google Analytics combined with Google Tag Manager to track traffic sources, visitor behaviour, and engagement across channels, including organic, paid, and social media.

CAC measures the total marketing spend required to acquire a new customer. Monitoring CAC ensures campaigns are cost-effective and aligned with revenue and profitability goals.

Align KPIs with your business objectives, set SMART (Specific, Measurable, Achievable, Relevant, Time-bound) metrics, and benchmark performance against past results or industry standards.

Yes, Google Tag Manager enables seamless integration with analytics and marketing tools, allowing businesses to track KPIs accurately, measure conversions, and optimise campaigns effectively.

KPIs should be monitored regularly, monthly or quarterly, depending on campaign scale. Continuous review helps identify trends, optimise performance, and align marketing efforts with changing business goals.