Grammar and mechanics

You should almost always write in the active voice, particularly if the user needs to do something.

While it’s generally best to avoid the passive voice, in certain situations it helps you sound softer without adding too many words. It’s especially useful for time-sensitive messages like payment confirmations and error messages. You can also use the passive voice to avoid referring to yourself or Stack Overflow.

Contractions make copy sound more human. Avoid contractions that sound awkward when you say them out loud, or are not commonly used in everyday conversation.

Use sentence casing for all headings and calls-to-action. Proper or trademarked nouns (e.g. countries, product names) should be capitalized. If a feature or product is unique to Stack Overflow, capitalize it (Stack Overflow for Teams, Stack Overflow Jobs).

Use American spelling for all public-facing content. When in doubt, check the Merriam-Webster dictionary for the preferred spelling of specific terms.

Let’s use the abbreviated version of “OK”. This is preferred to “Okay” and its variants. “OK” should be fully capitalized in every context. Tonally, it may be appropriate to use “OK” in an actionable button—if it isn’t used alone.

Refer to users as “you.” Don’t put words in their mouths with phrases that use “I” or “my.”

When getting consent or granting permissions, refer to users as “I.” In some cases (such as getting someone to grant permissions), refer to users as “I.”

When referring to Stack Overflow, use “we.” However, try to avoid inserting Stack Overflow into the content as much as possible.

Use “their” as a singular, gender-neutral pronoun when the gender of the subject is unknown or unimportant. Avoid using gendered terms.

Take extra care when using “login,” and “log in.” The former is a noun while the latter is a verb. Do not use “login” as a verb. The same logic applies to “signup,” “sign up.”

Don’t use ampersands (&) unless it’s part of a branded term. Spell out the word “and” instead.

Use apostrophes to represent omitted letters or numbers (can’t, you’re, ’90s) and to form possessives.

Avoid using colons unless you’re introducing a list. If you need to use a colon in a sentence, don’t capitalize the first word after it.

The ellipses (…) can be used in place of a missing piece of text (most commonly to show the deletion of words from a quote). Avoid using ellipses in text. It’s appropriate to use an ellipses in input placeholder copy. Use the real single character ellipsis unicode (…) instead of three periods (...).

Don’t use exclamation points unless something is really exciting! If you have to use one, limit yourself to one exclamation mark per page.

Use hyphens to combine two words that modify or describe the noun that follows, or join prefixes and suffixes when there are two vowels beside each other.

Use an en dash with no spaces in between (–) for a fixed range of numbers. Avoid using them in a sentence. Avoid using em dashes in microcopy.

Avoid using question marks wherever possible. Reword into affirmative statements wherever you can. It’s okay to use question marks if you don’t know the result of the question (“Did you forget your email?”).

Use quotation marks to define words (“Accepted answer”) or to quote text. Always use smart, curly quotes (“), not vertical, straight quotes ("). Single curly quotes (’) can be used when nested within a set of double quotes. Place punctuation marks inside quotation marks.

Use the oxford comma in sentences. Don’t use a comma to separate two distinct phrases (comma splicing). Use two sentences instead.

Don’t use periods in interface copy unless it’s a full sentence or description.

Avoid using semicolons. When connecting two closely related ideas, use a comma or write two sentences.

Buttons and links should be clear and predictable. People should be able to anticipate what will happen when they click or tap. Button and link text should be sentence case and action led (starting with a verb). To provide enough context, use a verb+noun format except for common actions like Save or Close.

All headings or subheadings should be concise, scannable, and sentence case. Don’t use periods at the end of headings. If a subheading is a full sentence, you may use a period.

When writing lists:

• Use a colon (:) to introduce an unordered list.
• Use sentence case.
• If any list item contains two or more sentences, punctuate all list items.
• If all list items are one sentence or fragments, don’t punctuate.