SLA vs SLO

SLA (Service Level Agreement) and SLO (Service Level Objective) are often confused but serve different purposes. SLAs are legal contracts with external customers that include financial consequences for breaches, while SLOs are internal targets used by engineering teams to guide service optimization. The key difference lies in accountability: SLAs have legal ramifications, while SLOs typically result in operational constraints like blocking deployments when error budgets are exhausted. SLAs are external-facing, less frequently revised, and simpler in technical detail but more complex legally. SLOs are internal, more technically detailed, and can be adjusted more frequently based on engineering needs.