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SLA Uptime/Downtime Calculator

Calculate SLA percentages, uptime, and downtime periods with industry standard examples

SLA Calculator
Uptime
Downtime
Service Level

Industry Standard SLA Examples

AWS EC2

99.99%

Amazon EC2 Service Level Agreement

Examples: AWS EC2, AWS RDS, AWS S3
Yearly Downtime: 52.56 minutes

Google Cloud

99.95%

Google Cloud Platform Compute Engine

Examples: Google Compute Engine, Google Cloud Storage, Google Cloud SQL
Yearly Downtime: 4.38 hours

Microsoft Azure

99.95%

Azure Virtual Machines

Examples: Azure VMs, Azure SQL Database, Azure Storage
Yearly Downtime: 4.38 hours

Cloudflare

99.9%

Cloudflare CDN and DNS services

Examples: Cloudflare CDN, Cloudflare DNS, Cloudflare Workers
Yearly Downtime: 8.76 hours

Stripe

99.99%

Stripe Payment Processing API

Examples: Stripe API, PayPal API, Square API
Yearly Downtime: 52.56 minutes

Twilio

99.95%

Twilio Communication APIs

Examples: Twilio SMS, Twilio Voice, SendGrid Email
Yearly Downtime: 4.38 hours

Enterprise Software

99.5%

Typical enterprise software applications

Examples: Salesforce, Office 365, Slack
Yearly Downtime: 1.82 days

Web Hosting

99.9%

Standard web hosting services

Examples: Shared Hosting, VPS Hosting, Dedicated Servers
Yearly Downtime: 8.76 hours

How to Calculate SLA

Basic SLA Formula

SLA % = (Total Time - Downtime) / Total Time × 100

Where Total Time is the measurement period and Downtime is the time the service was unavailable.

Uptime Calculation

Uptime = Total Time - Downtime
Uptime % = (Uptime / Total Time) × 100

Downtime from SLA

Downtime = Total Time × (100 - SLA%) / 100

Common Time Periods

Annual (365 days):
  • 99.9% = 8.76 hours downtime
  • 99.95% = 4.38 hours downtime
  • 99.99% = 52.56 minutes downtime
  • 99.999% = 5.26 minutes downtime
Monthly (30 days):
  • 99.9% = 43.2 minutes downtime
  • 99.95% = 21.6 minutes downtime
  • 99.99% = 4.32 minutes downtime
  • 99.999% = 25.9 seconds downtime

SLA Best Practices

  • Define clear measurement periods and exclusions
  • Include planned maintenance windows in calculations
  • Set realistic targets based on system architecture
  • Monitor continuously and report transparently
  • Include penalties and remedies for SLA breaches
  • Review and adjust SLAs based on actual performance

Frequently Asked Questions (FAQ)

What is an SLA and why is it important?
A Service Level Agreement (SLA) is a contract that defines the expected level of service availability, typically expressed as a percentage. It's crucial for setting expectations between service providers and customers, and often includes penalties for not meeting the agreed uptime.
How is SLA percentage calculated?
SLA percentage is calculated as: (Total Time - Downtime) / Total Time × 100. For example, if a service is down for 8.76 hours in a year (8760 hours), the SLA would be (8760 - 8.76) / 8760 × 100 = 99.9%.
What's the difference between 99.9% and 99.99% uptime?
The difference is significant: 99.9% allows for about 8.76 hours of downtime per year, while 99.99% only allows for about 52.56 minutes per year. This represents a 10x improvement in reliability.
What are typical SLA levels in the industry?
Common SLA levels include: 99.9% (8.76 hours downtime/year) for standard services, 99.95% (4.38 hours/year) for business-critical services, and 99.99% (52.56 minutes/year) for mission-critical systems like payment processors.
Is my data processed securely?
Yes, all calculations happen in your browser. No data is sent to any server, ensuring complete privacy and security of your SLA calculations.

About This SLA Calculator

This SLA (Service Level Agreement) calculator helps you convert between SLA percentages and actual uptime/downtime periods. It's essential for IT professionals, service providers, and businesses to understand the real-world impact of different SLA levels.

The calculator works both ways: you can input an SLA percentage to see the allowed downtime, or input actual uptime/downtime to calculate the resulting SLA percentage. This is particularly useful for capacity planning, SLA negotiations, and performance monitoring.

All calculations are performed locally in your browser - no data is sent to any server, ensuring complete privacy and security.