How much downtime does each uptime target allow?

Allowed downtime equals total minutes in the period times the failure fraction. For a 30-day month, 99.9% allows about 43 minutes, 99.95% about 22 minutes, and 99.99% only about 4 minutes per month. The tool calculates this automatically.

What is the difference between response time and resolution time?

Response time is how quickly the provider acknowledges an incident and begins work. Resolution time is when the issue is fixed. SLAs usually commit to response times because resolution depends on the complexity of each incident.

How are service credits calculated?

A common model gives the customer a fixed percentage of monthly fees for each full percentage point that availability fell below target, capped at 100% of monthly fees. This tool lets you set that per-point rate.

What should be excluded from the uptime measurement?

Scheduled maintenance announced in advance, force majeure, third-party network or DNS failures, customer-caused problems, and suspensions for non-payment are typically excluded so the provider is not penalised for events outside its control.

Is this a legally binding contract?

No. It is a structured template. Have it reviewed and adapted by a qualified professional before attaching it to a commercial contract.

SLA (Service Level Agreement) Builder

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Make availability promises measurable

A Service Level Agreement turns vague reliability promises into numbers both sides can check: a target availability percentage, the maximum downtime that implies, how fast the provider responds to incidents, and what the customer gets if the target is missed. This builder produces a complete SLA and does the downtime maths for you.

How it works

Availability is measured as a percentage of time the service was reachable:

Availability % = (Total minutes − Downtime minutes) / Total minutes × 100

From your chosen target the tool computes the error budget — the downtime you are allowed before breaching. For a 30-day month (43,200 minutes) the failure fraction is (100 − target) / 100, so 99.9% permits 43200 × 0.001 ≈ 43 minutes. Service credits follow a per-point formula: for each full percentage point below target, the customer earns the credit rate you set, capped at 100% of monthly fees.

Tips and notes

Pick a target you can actually meet — every extra “nine” is roughly ten times less allowed downtime and far more expensive to engineer. List your maintenance windows and force-majeure exclusions explicitly so honest outages don’t trigger penalties. Keep the escalation matrix short and name real roles. This is a template, not legal advice.