Frustrating issue of making effort and duration exactly the same

Hello Everyone,

I am relatively new to OmniPlan. I have been trying to go through the learning material on Lynda website. However, although I am no expert, I have been using OmniPlan on and off for over 2 years now. Never putting it to proper use.

I am planning a big project. The main resource will be 1 person, me. And there will be a few other people involved, I will end up doing 90% of tasks. Now the problem I am having is I want OmniPlan to show the exact plan or an accurate plan. So if I have a task start at 9am and last for 4 hours, I want it to finish at 1pm, because it is 4 hours long. Now when I enter the first task, OmniPlan is fine and does it right. However, when I get to the 3rd or 4th task, say the first task is 2 hours long, the next task is 3 hours long, then 3rd task is 3 hours long, and the 4th task is 3 hours long, and the resource is working a 12 hour day, then by the time I get to the 4th task if the effort says 4 hours the duration will say 3 hours and so on. It won’t match. I don’t need effort. I just need duration. I don’t really care about effort right now. I want my plan to show exact start time and duration. Thats all that matters to me. This one issue has been causing me a lot of frustration, to the point where I have been considering trying MS Project or Smart Sheet. OmniPlan has many features I like and want. If someone could help me with this I would be very grateful.

Thank you.


@workingnomads I’m sorry for the trouble! Have you been in contact with our Support team? They should be able to take a look at your file with you to determine why OmniPlan isn’t scheduling your tasks the way you’re expecting it to. Our Support team can be reached at or by phone Mon - Fri, 10am - 5pm Pacific at 1 (800) 315-6664 or 1 (206) 523-4152.

Is there a simple answer to this question. I’m not understanding it either.

@workingnomads did you figure it out?

Duration and Effort are sometime more and sometime less than each other no matter what resource allocation option is used.

duration input in the column doesn’t reflect the duration in the task view no matter what resource allocation option is used.

I type in a 4w duration into a task and it appears as 12 days in the task view even when there are no assigned resources to even change the effort.

Ultimately it’s very frustrating. Can you explain the principle behind effort and duration?

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Hi Workingnomads,
Did you ever get your problem solved? I have the same problem and I imagine others do too. Could you share what you have found about Effort and Duration being treated as exactly the same thing?


Same issue here, has anyone got an insight??

Hi ,

If you select
View, network diagram and then customise task labels you can switch out the effort part of the task label and replace it with duration.


Please, I’d like to understand which parameter should I set (Effort? Duration?) so that OP will move all of the dependent tasks by the same amount of days, when a predecessor’s task’s starting time is readjusted.

I already created almost three hundred tasks in an outline view (structuring initially “father>child & brothers” relations). Please note that I don’t need to adjust any resources (people) - because all of the tasks must be done by me.

Now I will have to do two things:

  1. Set hundreds of dependencies (mostly “this task only begins after that one is finished”);

  2. Set the estimated time for each task (this is my main question): in which field should I set the estimated duration of time the tasks will take, so that they correctly move in time proportionally when I adjust their predecessors start date? I guess I am confused because there are fields that affect a task’s starting date, some of them being relatted to “Effort” and other fields where we can input specific dates.

I read the manual but I’m a bit confused still. I’m really in a hurry due to this crazy-making times and it will take a long time to do all this planning, so I’m asking this question since I’m very new to OP.
Sorry if my question is too basic.

I will really appreciate your answer, due to this enormous project that I must adjust ASAP, so I can finally have an idea of the finishing date of the project.

And if all goes well, all tasks will be correctly moved in time without me having to set their start date, because all I know is their estimated duration. Their start dates will be affected automatically just by me readjusting the start time of their predecessors, right?

All the best to all of you!

Thank you very much!

It is not so difficult, Duration and effort are interlinked. When you have created the task you should assign a resource to the task and set the resource allocation button to : adjust task effort. That implies that if you change the assignment % the duration stays the same but the effort varies. What is important to realize is when you create the task you need to assign the right quantity of resources. Once created there is a link between the effort and duration which you can not change any more.

Thank you so much for your answer, rappa58. But please note that I wouldn’t want to set any resources (people) because all of the tasks will be done by me (also, I already created almost 300 tasks in outline mode - as stated above).

  1. Wouldn’t it work if I simply set the estimated duration for each task, without assigning any resource to it? It seems that it would be an immense waste of time if I am forced to assign the same resource to all of the tasks.

I’d like to simply readjust the start date of the first task and have the dates of all the following (dependent) tasks to readjust accordingly, automatically.

  1. Also, since tasks will certainly take different times to complete than I initially estimate, I’d like to freely change (as the project develops in time) the estimated duration of tasks to different values. Can I do that without problems? I got a bit worried when you said that certain parameters should be set initially and could not be changed afterwards.

Thanks a lot for your help!