The slash (/) is a common punctuation mark used to indicate alternatives, ratios, or connections. It is also known as a forward slash, virgule, or solidus. Unlike other punctuation marks, the slash has very specific rules regarding spacing and context. In most cases, you do not use spaces around a slash.
Core Function
The primary job of a slash is to replace the word or. It shows that two terms are alternatives or interchangeable.
Dear Sir/Madam (Sir or Madam)
Table of Contents
Indicating Alternatives (Or)
The most frequent use of the slash is to represent a choice between two words. It connects words or phrases that are mutually exclusive or interchangeable. In these instances, there is no space before or after the slash.
- He/she: Used when the gender is unknown.
- And/or: Indicates that one or both options are valid.
- Pass/fail: A grading system with two possible outcomes.
| Usage Type | Correct Example ✅ | Incorrect Example ❌ |
|---|---|---|
| Simple Choice | Each student must bring his/her ID. | Each student must bring his / her ID. |
| Combined Role | She is the owner/chef of the restaurant. | She is the owner-chef of the restaurant. |
“Per” and Measurements
In scientific, technical, and mathematical contexts, the slash signifies the word “per.” It expresses a relationship between two units of measurement. This is standard in both formal and informal writing.
- Speed: km/h (kilometers per hour)
- Price: $20/hour (20 dollars per hour)
- Density: g/cm³ (grams per cubic centimeter)
You also use the slash to separate the numerator from the denominator in written fractions when special formatting is not available (e.g., 1/2, 2/3).
Poetry and Song Lyrics
This is the only major exception to the “no spaces” rule. When you quote multiple lines of poetry or song lyrics within a single line of text, you must use a slash to mark the line break. You must place one space before and one space after the slash.
Quoting Poetry
Original text:
I wandered lonely as a cloud
That floats on high o’er vales and hills
Correct Citation:
“I wandered lonely as a cloud / That floats on high o’er vales and hills.” Correct ✅
Incorrect Citation:
“I wandered lonely as a cloud/That floats on high o’er vales and hills.” Wrong ❌
Dates
Slashes are the standard separator for numerical dates. The format depends on the region. No spaces are used.
- United States (MM/DD/YYYY): 01/25/2026
- UK/Europe (DD/MM/YYYY): 25/01/2026
- ISO Standard (YYYY/MM/DD): 2026/01/25 (Often uses hyphens, but slashes are accepted in some contexts).
Common Abbreviations
Several standard abbreviations incorporate a slash. These are often remnants of handwritten shorthand but are widely accepted in business and informal communication.Source-2✅
| Abbreviation | Meaning | Usage |
|---|---|---|
| c/o | Care of | Mailing addresses (leaves mail for someone at an address). |
| w/ | With | Informal notes or medical shorthand. |
| w/o | Without | Informal notes. |
| n/a | Not applicable | Forms and data tables. |
Slash (/) vs. Backslash (\)
These two symbols are often confused but perform completely different functions, especially in technology. The forward slash (/) leans forward; the backslash (\) leans backward.
- Forward Slash (/)
- Used for internet URLs and file paths in Unix/Linux/macOS.
- Example: correctornot.com/category/grammar
- Backslash (\)
- Used primarily in Windows file paths. It is rarely used in standard writing.
- Example: C:\Users\Admin\Documents
Frequently Asked Questions
Do I put a space before and after a slash?
Generally, no. You should not put spaces around a slash when indicating alternatives (yes/no) or ratios (km/h). The only exception is when quoting lines of poetry or song lyrics, where you place a space on both sides ( / ).
Is it okay to use “and/or” in formal writing?
It is acceptable in legal or technical documents where precision is required. However, in formal essays or academic writing, style guides often recommend rewriting the sentence to avoid “and/or” as it can look messy.
Can I use a slash in a file name?
What is the difference between a virgule and a slash?
There is no difference in function. “Virgule” and “solidus” are simply the technical names for the punctuation mark commonly called a slash.
{
“@context”: “https://schema.org”,
“@type”: “FAQPage”,
“mainEntity”: [
{
“@type”: “Question”,
“name”: “Do I put a space before and after a slash?”,
“acceptedAnswer”: {
“@type”: “Answer”,
“text”: “Generally, no. You should not put spaces around a slash when indicating alternatives (yes/no) or ratios (km/h). The only exception is when quoting lines of poetry or song lyrics, where you place a space on both sides ( / ).”
}
},
{
“@type”: “Question”,
“name”: “Is it okay to use \”and/or\” in formal writing?”,
“acceptedAnswer”: {
“@type”: “Answer”,
“text”: “It is acceptable in legal or technical documents where precision is required. However, in formal essays or academic writing, style guides often recommend rewriting the sentence to avoid \”and/or\” as it can look messy.”
}
},
{
“@type”: “Question”,
“name”: “Can I use a slash in a file name?”,
“acceptedAnswer”: {
“@type”: “Answer”,
“text”: “No. Most operating systems (Windows, macOS) forbid the use of slashes in file names because the system reads the slash as a directory separator. Use a hyphen (-) or underscore (_) instead.”
}
},
{
“@type”: “Question”,
“name”: “What is the difference between a virgule and a slash?”,
“acceptedAnswer”: {
“@type”: “Answer”,
“text”: “There is no difference in function. \”Virgule\” and \”solidus\” are simply the technical names for the punctuation mark commonly called a slash.”
}
}
]
}