Free · Technology
Availability Percentage and Downtime Budget
Convert availability to uptime and downtime over fixed daily, weekly, monthly and annual windows.
- Formula & worked example
- Private in your browser
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Calculator inputs
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How to use this calculator
- Enter the known values in the units shown. Results update as you type.
- Where results are editable, change one to solve backwards. Lock a value to hold it fixed.
- Use the worked example to check the method. Reset restores the starting fields.
Private by default
Inputs and results stay in this browser tab. Bookify does not upload or store the values you enter.
Formula and method
uptime day = 86314; downtime day = 86.400. The example uses the declared units and assumptions.
downtime_day = 86400 - (uptime* 24 *3600) ; downtime_week =604800 -( uptime * 168 * 3600); downtime_month = 2592000 - (uptime * 720 * 3600); downtime_year = 31536000- (uptime * 8760 * 3600); uptime_day = uptime* 24 *3600; uptime_week =uptime * 168 * 3600; uptime_month = uptime * 720 * 3600; uptime_year = uptime * 8760 * 3600; downtime_week_days = floor(downtime_week/(60*60*24)); downtime_week_hrs = floor((downtime_week - downtime_week_days * 60*60*24) / 3600); downtime_week_mins = floor((downtime_week - downtime_week_days * 60*60*24 - downtime_week_hrs * 3600) / 60); downtime_week_secs = one_way(downtime_week - downtime_week_days * 60*60*24 - downtime_week_hrs * 3600 - downtime_week_mins * 60); downtime_month_days = floor(downtime_month/(60*60*24)); downtime_month_hrs = floor((downtime_month - downtime_month_days * 60*60*24) / 3600); downtime_month_mins = floor((downtime_month - downtime_month_days * 60*60*24 - downtime_month_hrs * 3600) / 60); downtime_month_secs = one_way(downtime_month - downtime_month_days * 60*60*24 - downtime_month_hrs * 3600 - downtime_month_mins * 60); downtime_year_days = floor(downtime_year/(60*60*24)); downtime_year_hrs = floor((downtime_year - downtime_year_days * 60*60*24) / 3600); downtime_year_mins = floor((downtime_year - downtime_year_days * 60*60*24 - downtime_year_hrs * 3600) / 60); downtime_year_secs = one_way(downtime_year - downtime_year_days * 60*60*24 - downtime_year_hrs * 3600 - downtime_year_mins * 60); uptime_week_days = floor(uptime_week/(60*60*24)); uptime_week_hrs = floor((uptime_week - uptime_week_days * 60*60*24) / 3600); uptime_week_mins = floor((uptime_week - uptime_week_days * 60*60*24 - uptime_week_hrs * 3600) / 60); uptime_week_secs = one_way(uptime_week - uptime_week_days * 60*60*24 - uptime_week_hrs * 3600 - uptime_week_mins * 60); uptime_month_days = floor(uptime_month/(60*60*24)); uptime_month_hrs = floor((uptime_month - uptime_month_days * 60*60*24) / 3600); uptime_month_mins = floor((uptime_month - uptime_month_days * 60*60*24 - uptime_month_hrs * 3600) / 60); uptime_month_secs = one_way(uptime_month - uptime_month_days * 60*60*24 - uptime_month_hrs * 3600 - uptime_month_mins * 60); uptime_year_days = floor(uptime_year/(60*60*24)); uptime_year_hrs = floor((uptime_year - uptime_year_days * 60*60*24) / 3600); uptime_year_mins = floor((uptime_year - uptime_year_days * 60*60*24 - uptime_year_hrs * 3600) / 60); uptime_year_secs = one_way(uptime_year - uptime_year_days * 60*60*24 - uptime_year_hrs * 3600 - uptime_year_mins * 60)
Worked example
Enter these known values and leave the other values blank.
- Uptime
- 99.9 %
- Daily
- 0:1:26.4 hrs / min / sec
- Weekly
- 0:0.168 days / hrs
- Monthly
- 0:0.72 days / hrs
- Yearly
- 0:8.76 days / hrs
Assumptions and limitations
- This arithmetic budget uses fixed windows of 24 hours,7 days,30 days and 365 days, not calendar-month lengths or a specific service-level agreement. Zero and 100 percent availability are valid endpoints.
- Editable controls retain the supported captured branches; clear an unknown and supply independent known quantities. A singular or underdetermined inverse may remain incomplete.
Common questions
What assumptions apply?
This arithmetic budget uses fixed windows of 24 hours,7 days,30 days and 365 days, not calendar-month lengths or a specific service-level agreement. Zero and 100 percent availability are valid endpoints.
Can I solve an unknown?
Clear an editable unknown and provide enough independent quantities in the displayed units. Discrete counts must remain whole numbers.
References
Availability covers the closed interval0–100 percent; uptime and downtime durations may legitimately be zero at its endpoints.