Knowledge Base

Estimating in Ranges

Entering Estimates

Estimates are entered via the task’s Edit Panel under ‘Remaining’.  To limit the hours of availability allocated to the task per day, set a Daily Limit.

To add or update an estimate, simply enter your best-case and worst-case estimates for how many hours or days it will take you to complete the task. The two values should represent a range of effort in which you’re about 80% confident that the actual effort to complete the task will be between.

You can enter estimates in any of the following units by adding the unit letter after the number like this:

  • 2w (for 2 weeks)
  • 2d (for 2 days)
  • 2h (for 2 hours)
  • 15m (for 15 minutes)

The number you enter will be converted to the workspace default unit. (Only your workspace owner can change the workspace default unit.)

Remaining Effort

Estimating work in terms of effort is very different from guessing the number of calendar days until this task will be done. Ranged estimates in LiquidPlanner represent the amount of remaining work there is for a task. If a task is estimated at 5-10 days, that means you expect to put in 5-10 full days of work in order to complete it; you’re not specifying when that task will be done because LiquidPlanner will figure that out for you! Since there are tons of other factors like dependencies, vacations, and availability that can impact the completion of a task, making a guess about the finish date just isn’t good practice. By estimating the amount of effort the work will take, LiquidPlanner can calculate realistic schedule dates based on priorities and resource availability.

Why estimate in ranges?

The single-point estimates (i.e., “10 days”) that most software programs use are usually padded guesses instead of realistic estimates.

Ranged estimates capture the amount of uncertainty associated with each task. If the range is quite large, the amount of uncertainty is high. If the range is small, the task duration is relatively certain.

LiquidPlanner sees each range as a bell curve and uses it to calculate an expected completion date. The set of ranged estimates in your project provides the data LiquidPlanner uses to statistically determine all of the possible schedule outcomes. This data appears on schedule bars in the Projects tab.

Estimating in realistic ranges is one of the single best things you can do to improve your project outcomes.


Ranged estimation will change your team’s perspective on work and scheduling and move conversations from uncomfortable negotiations to open and honest dialogue about requirements and ways to work together constructively to get rid of uncertainty.

Estimating in ranges is a transformative shift forward in project management thinking and is an excellent method for managing risk.

When you make ranged estimates, you should try to be at least 80% confident that the actual outcome will fall in the range. The easy way to think of this is as reasonable best-case and worst-case estimates. LiquidPlanner translates these effort ranges into schedule ranges and does statistically correct rollups for the total expected effort on projects.

To learn more about how to monitor work with wide ranged estimates, take a look at our guide about managing risk and uncertainty in your project plan.


Related Articles

Building a Best Case/Worst Case Schedule
Breaking Down a Project: How Much Detail is Enough?
The Edit Panel
Setting a Daily Limit

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