Book editors do a lot more than check for grammar and spelling.
A big part of a copyedit service is to ensure your manuscript is written consistently, concisely, clearly, and correctly.
CONSISTENTLY:
This does involve grammar and spelling, but you want to make sure you have consistent style choices throughout the manuscript.
For example, a copyeditor will check for the consistent use of the Oxford comma, but will also make sure each chapter heading is consistently titled and numbered, your characters’ names are spelled consistently, your timeline points do not have major continuity errors, and italics are used in a specific way.
CONCISELY:
This involves editing for redundancies and often posting a comment in the margins asking the author to confirm that something can be revised.
A copyeditor will also note and potentially revise repeated phrases that a reader may pick up on.
For example, the word “uncanny” is used twice in two paragraphs and feels redundant, so the copyeditor will suggest a revision.
CLEARLY:
This includes a lot of things, including wordiness, confusing word choices, and basically anything that could potentially confuse a reader.
For example, a copyeditor may note when a particular sentence is not making sense and offer a suggestion for clarifying the meaning.
CORRECTLY:
This can include grammar usage according to the Chicago Manual of Style, correct spelling according to Merriam-Webster, conscious language choices, light fact-checking, and continuity within the story’s own logic.
For example, a copyeditor will edit a sentence that has a misplaced modifier, but will also correct a sentence that states the Titanic sank in 1913.
I’ve had clients use grammar-checking softwares for self-editing prior to hiring me, and I still made anywhere from 1,000–1,900 revisions on their novel-length manuscript.
It can definitely be helpful when a client uses one of these softwares in the self-edit stage, because it can catch some of those nitpicky things so I can concentrate on other things.
But it just can’t be a replacement for a human editor looking at the manuscript.
