Parentheses vs. Brackets — Uses and Examples

Parentheses and brackets

A set of parentheses are a pair of punctuation marks "( )" that set off extra information within a sentence or paragraph. Square brackets' “[ ]” primary function is to indicate a change within a direct quotation, whether it is an addition of a word, alterations in grammar, or modified capitalization.

Additional parenthetical material typically includes short asides or background information that provides supplemental content yet is not entirely essential. If the material is crucial to the meaning of the sentence, use commas, colons, or dashes instead.

How to use parentheses and brackets

When using parentheses, the following rules apply:

Rule 1: Use parentheses to encompass additional information that provides clarification. This information may be a single word, a phrase, or an entire sentence. If the added material comes at the end of the sentence, place the punctuation mark after the closing parenthesis.

Rule 2: Place periods, question marks, and exclamation points inside the parentheses only when they enclose a complete sentence.

Rule 3: Parenthetical information is not part of the subject of a sentence.

Rule 4: Commas should typically follow parentheses rather than precede them.

Rule 5: Place acronyms or abbreviations in parentheses after spelling them out for the first time.

Rule 6: Enclose a parenthetical citation in parentheses at the end of a sentence, after the closing quotation mark (if necessary), and before the final punctuation.

When using brackets, the following rules apply:

Rule 1: Use brackets around information added to a quotation that explains or comments on the quoted material.

Rule 2: If quoting information from the middle of a sentence, capitalize and bracket the first letter of the first word if the material still creates a complete sentence.

Original Quote: "Not all who wander are lost."

Original Quote: "Because I think that life is far too important a thing ever to talk seriously about it."

Rule 3: If a quotation contains a spelling or grammar error, insert and italicize the word sic in brackets after the error. The use of sic indicates that the writer recognizes the error yet wants to keep the quotation true to its original form.

Examples of brackets and parentheses

The following sentences correctly incorporate the use of parentheses:

• We finally made it home well after dinner (around 9:00 p.m.).

• Everyone had a great time at the beach. (The weather was perfect.)

• Troy (with George by his side) was ready to compete.

• After walking on stage to the podium (a little over 50 feet away), Wendy gave her speech.

• According to the Bureau of Labor and Statistics (BLS), there will be a demand for more nurses.

• FDR exclaimed that December 7, 1941, "will live in infamy" (Roosevelt).

• Out of 100 students, 89 voted to change the school's mascot (Miller).

The following sentences correctly incorporate the use of brackets:

• The host told the rest of the group. "Darren and his sister [Josie] will be joining us this evening."

• Harper Lee's Atticus Finch tells his son that "[r]eal courage is when you know you're licked before you begin, but you begin anyway and see it through no matter what."

  • Original Quotation: “I wanted you to see what real courage is, instead of getting the idea that courage is a man with a gun in his hand. It's when you know you're licked before you begin, but you begin anyway and see it through no matter what.”

• According to J.D. Salinger's Holden Caufield, "[S]ay something no one understands and they'll do practically anything you want them to."

  • Original Quotation: “All you have to do is say something nobody understands and they'll do practically anything you want them to.”

• "You'll find you're [sic] luggage has been taken to your room," said the clerk at the front desk.

• Oliver couldn't believe that "hipopotamuses [sic] spend most of their time underwater."