*Developmental (or Content) editing 1–5 ms pgs/hr $40–60/hr
*Substantive or line editing 1–6 ms pgs/hr $40–60/hr
Sensitivity reading 1-10 ms pgs/hr $30-60/hr
Basic copyediting (proofreading) 5–10 ms pgs/hr $30–40/hr
Heavy copyediting (proofreading) 2–5 ms pgs/hr $40–50/hr
*This is the kind of editing that your cute and cuddly Writing About Writing blogger Chris sometimes does freelance. Please don't ask about copyediting. It's not pretty.
I will periodically update these prices.
Of course, even the range of these prices is not comprehensive. Unless you're getting a deal, I'd worry about the skill level of your editor if you're finding something at a substantially lower price than these (say more than $10 less). You might have found one of those amazing deals or someone who hasn't realized what they're worth yet, but it's just as likely the quality of their editing might not be professional. Of course you can find lots of stuff that's more expensive, even WAY more expensive. Everything from services that combine line and copy editing, charge $150/hr (but you get your stuff back by the next day), to writers whose names you might even recognize who will read your stuff (usually for $100-$200/hr or even more) and give you some feedback. (It's not necessarily worth that much more, but you get to say "Author McRecognizablename edited the first part of my book.") Just be careful. If you're paying much more than these prices, there should be a damned good reason, or you might be getting fleeced.
Developmental/Content editing: This is the big stuff. The character arcs that aren't working. The scenes that are redundant or dead air. The problems with pacing. The writing that seems stiff. The confusing setting. The tone that shifts. The dialogue that has no heat. The ham-handed exposition. This is the level of editing where you don't get told to make small changes (these people won't even circle a typo), but rather huge, massive ones. ("I would cut out this whole part. That entire character isn't working. Your story really begins at chapter 3.") It can be TOUGH to hear this about something you poured so much into.
This means this is also the level of editing most writers tend to avoid when they are first starting out and a little convinced that they are sitting on a masterpiece....or at LEAST will never have to do this kind of editing. (Spoiler: We all do.) It is paradoxically the hardest and slowest and most important level of editing to crafting a good piece of fiction.
Fortunately for your pocketbook, a handful of trusted peer review can save you from round after round of developmental/content editing. If you're writing the great American novel, you might want to have a professional take the last pass, but the more you trust your peer reviewer cohort, the more you can exchange your own feedback on their shit for the heavy lifting.
Substantive/Line editing: This is editing that is somewhere between the nuts and bolts of grammar and the lofty craft of fiction. It deals with the skillfulness of the writing itself. It concerns itself with "Is there a better way to word this?" The paragraph structure that is too monotonous. The sentence rhythm that relies on too many multiple clauses and not enough simple sentences for emphasis. The use of too many adverbs. A better word than that one for what you're trying to describe. Making it clearer what the action is, who is talking, or what they are trying to say.
When you change the font to read something with fresh eyes or try to read it out loud to yourself, this is the level at which you are hoping to catch mistakes.
Sensitivity Reading: This level of editing can weave throughout the other levels, even conceivably going into grammar if someone's speech patterns are reflected in their language. This is basically an editing pass for people who want to get their portrayals of typically-marginalized groups right without falling into cliché tropes or harmful stereotypes (even unintentionally). It may possibly point out how badly a work seems to be MISSING any kind of diversity. It is also useful to avoid a this-alien-race-is-a-stand-in-for-this-Earth-culture or the everyone-just-has-white-people-values-in-the-future trope. In an awful lot of "bold" science fiction written by men, for example, the women are still housewives and secretaries. Basically the more axes of privilege someone is on (white, male, cis, het), the more they should consider getting a sensitivity reader if they don't want to have an unintended impact that––post-publication––turns into the kind of criticism they never wanted.
Note: It would be extraordinarily INsensitive to try to get this sort of editing for free. You are literally asking someone to do something called "emotional labor" for you on a grand scale (you can look that up if you want to understand it a little better) People doing uncompensated emotional labor for hours and hours so that privileged folks (like straight white dudes) can understand "What's racist/sexist/homophobic about THAT?" is EXPLICITLY one of the problems of unequal power dynamics in our society. So pay them or barter something WELL worth it, but compensate them for this shit.
Copyediting/(Proofreading*): This editing gets into the grammar. Word form. Word meaning. Punctuation. Word order in some cases. Verb tenses. All that good gracious shit that you learned the names of in high school and then forgot but probably know better than you think you do if you're reading anywhere near enough to be a writer in the first place. We all make mistakes and a second set of eyes is vital for anything you want to submit. (And as the guy who has gotten more than a few shitty emails about my own grammar mistakes including not a few unkind words as regard to my ability to pass 11th grade, I would recommend it on anything you put out into the world at ALL if you can swing it.)
Copyediting tends to go faster the better copy is when it's received, so someone who has done their due diligence cleaning up their own copy can get several more pages per hour out of a copyeditor than someone who hands them a train wreck. Given that on a novel, this could be over a thousand dollars in editing fees, it's worth learning to clean up your own glaring grammar errors and hope that an editor just catches the few that get past you.
*That sound you just heard was everyone in the publishing industry clearing their throat. Though used 100% interchangeably in much modern vernacular and in most places that you'll try to find editors to hire, if you're elbow-rubbing in old-school or "official" publishing circles "proofreading" is often referred to only as the final pass before publication to catch the last of the mistakes before something goes to print. (It literally has to do with the proofs [or "galley proofs"] that typically had extra wide margins for notes, but are really not used anymore because the technology has changed.) In modern parlance, "proofreading" is a last step to clean up formatting errors and such. However, most people who aren't in the publishing industry mush the terms together and use them interchangeably (descriptive language being what it is) because they both become important at the end of the full editing process. No editor will be UNABLE to understand what you want if you ask them to "proofread" your manuscript (nor will they mock you for not knowing industry-lingo rather than using the word the same way every high school teacher on earth does when they tell you to "proofread carefully"). Strictly speaking though, proofreading should be only your very last step before publication (and looks for different kinds of mistakes) and is distinct from copyediting in that regard.