Accurate estimation is an important factor in running a successful business (or department). Whether you are paid by the hour or by the project, you need to have a reasonably good idea of how long you (or someone else) will take to edit a document. Even if money isn’t a problem, time may well be. The time that editing takes is related to another question: how many writers can an editor support?

Editors know (though their clients and managers may not) that “how long” depends very much on what level of editing is required. A detailed, heavy edit requiring major rewriting is obviously going to take a lot longer than a light copy-edit. So the first thing you need to do is clarify exactly what the client wants. (Be prepared to negotiate the “want list” when, as almost always happens, the client decides your initial estimate is too long and too expensive.)

Here are some of my editing estimates, based on my personal experience. They are within the range suggested by writers such as Carolyn Rude (Technical Editing, second edition, 1998), JoAnn Hackos (Managing Your Documentation Projects, 1994), and others.

Some assumptions in the estimates:

1. A “standard page” contains 500 words. If a document contains a lot of illustrations, it has fewer words per page, but I still have to give the illustrations some attention, so I try to take that into account when people give me page counts. For example, if someone tells me the document has 350 pages, most of which contain one screen shot, I may decide that 1 document page equals 2/3 of a “standard” page and adjust my estimate accordingly. If the paper size is unusually small or large, a document page may be more or less than a standard page.
2. I am typing my comments and changes into the file, not writing on paper. (I usually work faster that way, though not everyone does.)
3. I am marking every occurrence of a change, not instructing the writer to “find and change all instances of (whatever).”

Full substantive (heavy) edit, possibly including some rewriting: 1-2 pages per hour

Medium edit: 4-6 pages per hour

Light edit (skim document, correcting obvious errors in spelling, grammar, punctuation, consistency and completeness): 8-10 pages per hour

Final or production edit: 20 pages or more per hour (varies widely depending on what’s involved)

For online help, if link-checking, index editing, and “is it helpful” analysis is involved, I would use the lower range of the estimating metrics. Help can be very fiddly and time- consuming to check, as you need to use a compiled file (if at all possible) but enter your edits into an uncompiled file.

(Remember to convert the number of help topics to page- equivalents. A commonly-used conversion factor is 1 help topic equals 0.5 page; field-level help, pop-up glossary terms, and other short help topics are each equivalent to 0.25 page.)

For Web pages and Web sites, I use the same metrics as for online help.

What is your experience?

I am very interested to hear about others’ experiences: do my numbers seem too high or too low for your situation? What’s different about the materials you work with, or the conditions you work under?