Mistakes happen. But mistakes with grammar, spelling, or punctuation are preventable. Content riddled with grammatical errors looks sloppy and unprofessional and it immediately undermines the credibility of the information we're sharing.
Capitalization
Capitalize proper names, geographic terms, historic episodes, and words derived from proper nouns.
Don't capitalize the first word after a colon or semicolon unless it's a proper noun.
Don't use ALLCAPS unless you are writing an acronym.
Use lowercase for cardinal directions.
Capitalize titles preceding names, but use lowercase after names.
Example: Marketing Manager Jane Doe; Jack Doe, marketing manager
Use all lowercase when writing out an email address or website URL.
Capitalize the word "room" only when used with the number of the room.
Example: The panel will be held in Room 315.
Avoid capitalizing words like "federal" or "state" unless the word is part of a formal name.
Capitalize the word "Internet."
Punctuation
Ampersands
Don't use '+' to mean 'and'.
Apostrophes
When making a possessive from a noun ending in -s, use only an apostrophe.
Pluralize an acronym by adding -s.
Example: These VIPs have early access.
Commas
Always use the Oxford or serial comma when writing lists.
Example: We value strong communication skills, bias for action, and experience in SaaS.
Dashes and hyphens
Use an em dash (—) to offset an aside.
Use spaces before and after em dashes.
Use an en dash (–) to connect a range of numbers or dates.
Don't use spaces before or after en dashes.
Exclamation marks
Don't use multiple exclamation marks.
Percentages
With numerals, use '%' instead of spelling out 'percent'.
Example: Let’s do this 100% of the time.
Periods
Don't use periods in common country acronyms.
Quotation marks
Nested quotes should be enclosed by single quotation marks.
Punctuation goes within the quotation marks when it's part of the quoted material.
Date and Time
Currencies and money
For currencies, use the symbol-amount format without spaces in between.
Example: $10,000; €5.50
Don't use periods in currency abbreviations.
Example: USD, not U.S.D.
Write out million, billion, and trillion in full.
Example: $5 million
When writing out a monetary value, use commas to separate millions and thousands and decimal points to separate units and subunits.
Example: $1,000.50
Dates, months, and years
For short dates, use MM/DD/YYYY (without leading zeros).
Example: 12/25/1905 or 3/9/2019
For long dates, use Month DD, YYYY (without leading zeros).
Example: December 25, 1905
When including the day of the week in a date, place a comma after the day.
Example: Friday, December 25
To abbreviate days of the week, use longer abbreviations.
Example: Mon, Tues, Weds, Thurs, Fri, Sat, Sun
Don't use ordinal suffixes on dates.
Example: December 1, January 3, October 5
Numbers, fractions, and units
Spell out a number when it begins a sentence.
Example: Twelve days are left until the end of the quarter.
Always spell out numbers 0-9.
Use commas to separate thousands and millions in large numbers (and periods to separate units from subunits).
Example: 1,000
For telephone numbers, use parentheses for area codes, and a hyphen between the final two sets of numbers.
Example: (415) 400-5299
For units of measure, don't leave a space between between the number and the unit, use lowercase letters, and don't use punctuation.
Example: 25kg
When writing a decimal, include a leading zero before the decimal point.
Time and timezones
Write A.M. and P.M. in lowercase, don't include a space after the hour, and don't use periods between the letters.