I prepared this a few years ago and wanted to repost the link.
You can edit this sheet in Google docs or download it. All you need to do is edit the fields in yellow and the spreadsheet will automatically calculate estimated times at the key points on the course so your family and friends know approximately when to look for you. I set it up with estimates for “fast” and “slow” to provide a range of times. I don’t have a setting for “complete meltdown on the run,” however. You’re on your own to predict that.
The second time gives estimates for the men and women leading pros.