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The Art of CTO SLA Generator creates service level agreements with appropriate uptime targets, response time commitments, escalation procedures, and penalty terms.

What SLA should we commit to?

Tiered targets, penalties and terms as a document you can send.

About 10 min · Generator · Free

About this toolWhy it matters, common mistakes, FAQ

What Can You Actually Commit To?

An SLA is a contractual promise about a system's behaviour, often signed by people who have not measured it. Once committed, it constrains architecture, on-call and roadmap for the life of the contract.

Numbers are chosen because they look reassuring in a sales conversation. Three nines and four nines are different operational disciplines with different headcounts, and the difference is agreed in a meeting that includes no engineers.

Questions CTOs ask

What is the difference between SLA, SLO, and SLI?
SLIs (Service Level Indicators) are the actual measurements — request latency, error rate, throughput. SLOs (Service Level Objectives) are the internal targets you set for those indicators — "99.9% of requests will complete in under 200ms." SLAs (Service Level Agreements) are contractual commitments with customers that include consequences for missing targets — financial credits, contract termination rights. Your SLOs should be stricter than your SLAs to provide a buffer, and SLIs are how you measure compliance with both.
What uptime percentage should an SLA guarantee?
SLA uptime targets should reflect your actual architecture capability minus a safety buffer. 99.9% (8.7 hours downtime/year) is appropriate for most B2B SaaS. 99.95% (4.4 hours/year) is suitable for business-critical applications with redundant infrastructure. 99.99% (52.6 minutes/year) requires multi-region active-active architecture and is typically reserved for infrastructure providers. Never promise 100% — it is architecturally impossible and creates unlimited liability. Start with a conservative SLA and tighten it as your reliability track record improves.
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