Proofreading marks and editing symbols: a complete chart

Proofreading marks work in pairs. A small mark in the line shows where a change goes, and an instruction in the margin beside that line says what the change is: a caret under the line and the missing word in the margin, a stroke through a word and the delete sign beside it. Most American publishers follow the chart in The Chicago Manual of Style (figure 2.6 in the 18th edition, 2024), which has 42 marks in three groups: operational signs, typographical signs and punctuation. All of them are below, described in words, with what to do instead when the proof is a Word file, a Google Doc or a PDF.

How proofreading marks work

A proof is typeset and single-spaced, so there is no room between the lines for handwriting. The proofreader puts a small mark at the exact spot in the text and writes the instruction in the nearest margin, on the same line. Whoever makes the corrections, a typesetter or a designer or the author, scans down the margin, finds each instruction and looks along that line for its mark. A few habits keep this readable:

• One instruction per mark, in the nearest margin. When a line has several corrections, write them left to right in the order the marks appear and separate them with slashes.
• Circle instructions, not insertions. A circled ital means set in italic. The same letters without a circle would be typeset as a word.
• Mark the smallest unit that is wrong. A typo gets a mark through one letter; a style change gets a line under the whole word or phrase.
• Use a color that stands out from black type. Red is the traditional choice. Write clearly enough that a stranger could follow it.
• Ask questions as questions. A query to the author goes in the margin, circled and phrased so no one could set it by mistake: "Smith or Smyth? See p. 12."

Copyediting marks vs. proofreading marks

The symbols are largely the same; the placement is not. Copy editing happens on the manuscript before it is typeset. On paper that manuscript is double-spaced, so the editor writes changes directly in the text: a caret with the new word above it, a line through a phrase, no margin note. Proofreading happens on the typeset pages, and its job is narrower. It checks the proof against the edited manuscript and the editor's style sheet, catching typos, bad breaks and inconsistencies. Late changes are expensive because a single added word can reflow a paragraph and push lines onto the next page, so a proof is not the place for rewriting. That belongs to line editing, long before.

Operational marks: delete, insert, move

Operational marks change what is on the page or where it sits. The margin entries follow the Chicago chart; the in-text marks are the common way to point at the spot.

Delete, insert and space

Paragraphs, position and order

Type style marks

Typographical marks keep the words and change how they are set. The underlines come from handwritten and typewritten manuscripts, where a line under a word was how you asked for italic, and they work the same way on a proof.

Marks for punctuation and dashes

To add punctuation, put a caret in the text where it goes. To replace a wrong mark, put a slash through it. Either way the margin says which mark you want, drawn so it cannot be mistaken for a stray speck or for another mark.

Dashes deserve a slow look on every proof. Word processors turn typed hyphens into dashes automatically, not always the right kind, and a hyphen, an en dash and an em dash look alike at a glance. If you are unsure which belongs where, the em dash and en dash entry has the short version.

A marked-up proof, line by line

Here is a short passage as it came back from typesetting, with seven errors in five lines. The table shows how a proofreader would mark each one and what the margin of each line ends up holding.

Digital equivalents of the marks

Most proofing now happens on a screen, and the method depends on whether you can edit the file. In Word and Google Docs you make the change itself and the software records it: Track Changes in Word (Review, then Track Changes) shows insertions underlined in color and deletions struck through, and Suggesting mode in Google Docs (the Editing menu at the top right, then Suggesting) does the same. A PDF proof cannot be edited, so you annotate it, and the logic of the paper marks returns: the position says where, the comment says what.

If you write in plain text or Markdown, CriticMarkup is a small convention for the same job: additions, deletions, substitutions and comments written with braces, readable in any text editor. The first two lines of the proof above, with a query added, would look like this:

The {++*++}Invicta{++*++} left Calais at nine,{>>Query: a.m. or p.m.?<<} and by ten
the {--the --}coast of {~~england~>England~~} was a gray smudge behind them{++.++} Ada

American and British marks

The Chicago chart is the usual American reference. British publishers work from the British Standard BS 5261, and the two differ more in drawing than in substance. The British marks use more symbols and fewer English abbreviations (stet, for example, can be a tick in a circle), each margin instruction is closed with a slash, and a long insertion is keyed with a letter in a diamond, in the text and in the margin, with the new text written at the foot of the page or on a separate sheet. An international standard, ISO 5776, sets out symbols for text correction too, and publishers in other languages use their own variants.

Proofing your own pages in Strokes

Writers who lay out their own books still need a proof pass, and it works best on real pages. Strokes has a page view with margins and page numbers, so you can export a PDF, mark it up on paper or in a PDF reader, and then make the fixes in the document. Its version history saves versions automatically and on demand; save one before you start, and you can preview any earlier version with the changes marked and restore it in one click.

For a first sweep before the human read, select a passage, press ⌘K and ask for typos to be fixed in place, or ask the AI Assistant to list errors in a chapter. Agent mode shows every change it makes for you to review and accept. The page setup a submission needs is in how to format a manuscript.