The minus sign (−) receives its own special treatment because it denotes a mathematical function and thus does not belong to standard English grammar. Below are some examples highlighting the subtle differences between the minus sign and en dash.
This table highlights how the minus sign and the en dash differ among fonts. The minus sign sits slightly higher up than the en dash in Times New Roman font.
| Dash symbol | Minus sign (correct) | En dash (incorrect) |
|---|---|---|
| Serif, e.g. Times New Roman | 12 − 4 = 8 | 12 – 4 = 8 |
| Sans serif, e.g. Calibri | 12 − 4 = 8 | 12 – 4 = 8 |
See the differences in the zoomed image:
| Minus sign (correct) | En dash (incorrect) |
|---|---|
| 12 – 4 = 8 | 12 – 4 = 8 |
| 12 – 4 = 8 | 12 – 4 = 8 |
En dashes (–)
As a Uni-edit editor in science research, including biology, medicine, and genetics, I often encounter en dashes because of their close relationship with scientific content, such as numbers and data. The name ‘en dash’ originates from the width of the lower-case ‘n’ character typically used in typeface (fonts) (see below).
En dash
n
–
En dashes are common in all disciplines, but it’s not until we focus on their direct relationship with numerals and some scientific notation that we can begin to appreciate their usage, better understand their meaning, and correctly apply them to everyday grammar.
When defining the space between page numbers. We don’t insert spaces on either side of the en dash because the en dash represents a range of values starting from the first and ending on the last value.
| Correct example of en dash for page numbering | Incorrect examples |
|---|---|
| Please read pages 45–66, including Sections i–iv. | Please read pages 45-66, including Sections i-iv. Incorrect because a hyphen is used, which is too short. Please read pages 45 – 66, including Sections i – v. Incorrect because spaces are surrounding the en dash. |
| Bernays, E.A. (1986) Diet-induced head allometry among foliage-chewing insects and its importance for graminivores. Science, 231, 495–497. | Bernays, E.A. (1986) Diet-induced head allometry among foliage-chewing insects and its importance for graminivores. Science, 231, 495-497.
|
Between dates in chronological order:
| Correct example for en dash for years | Incorrect examples |
|---|---|
| Kennedy’s presidency (1961–1963) marked an extraordinary era. | Kennedy’s presidency (1961-1963) marked an extraordinary era. Incorrect because a hyphen is used, which is too short. |
| Some considered the 1999–2001 period a technological time bomb. Some considered the 1999 to 2001 period a technological time bomb. Some considered the ‘99 to ‘01 period a technological time bomb. | Some considered the 1999-2001 period a technological time bomb. Incorrect because a hyphen is used, which is too short. |
Letters in an indexing scheme:
| Correct example for en dash for indexing | Incorrect examples |
|---|---|
| Section 1–i. | Section 1-i. Incorrect because a hyphen is used, which is too short. |
| Statute 144–A. | Statute 144-A. Incorrect because a hyphen is used, which is too short. |
Between time frames:
| Correct example for en dash between time frames | Incorrect examples |
|---|---|
| The starting time is 6:30–6:45 PM. | The starting time is 6:30-6:45 PM. Incorrect because a hyphen is used, which is too short. The starting time is 6:30 PM-6:45 PM. Incorrect because a hyphen is used, which is too short, and ‘PM’ interrupts the range of values. |
| I work best at 4–4:30 PM. | I work best at 4-4:30 PM Incorrect because a hyphen is used, which is too short. |
Generally, we can use an en dash between any range of values. Here, the en dash replaces the need to describe the range of values. Therefore, we do not mix ‘from’ and ‘between’ with an en dash.
| Correct examples for ranges | Incorrect examples |
|---|---|
| We’re closed January–March. We’re closed from January to March. We’re closed from January until March. We’re closed between January and March. | We’re closed January-March. Incorrect because a hyphen is used, which is too short. We’re closed from January–March. Incorrect because ‘from’ shouldn’t be used in conjunction with an en dash. |
| The temperature is 17°C–19°C. The temperature ranges from 17°C to 19°C. The temperature is between 17°C and 19°C. | The temperature is 17°C-19°C. Incorrect because a hyphen is used, which is too short. The temperature is from 17°C–19°C. Incorrect because ‘from’ shouldn’t be used in conjunction with an en dash. |
| The pressure increased 10%–15%. The pressure increased from 10% to 15%. The pressure increased between 10% and 15%. | The pressure increased 10%-15%. Incorrect because a hyphen is used, which is too short. The pressure increased between 10%–15%. Incorrect because ‘between’ shouldn’t be used in conjunction with an en dash. |
| Please refer to pages 75–110. Please refer to pages 75 and 110. This example suggests only pages 75 and 110, and not any number in between. | Please refer to pages 75-110. Incorrect because a hyphen is used, which is too short. |
| From 75 to 110. Between 75 and 110. | From 75–110. Incorrect because ‘from’ shouldn’t be used in conjunction with an en dash. From 75-110. Incorrect because a hyphen is used, which is too short. |
| Here are the figures for 1999–2000. Here are the figures from 1999 to 2000. Here are the figures between 1999 and 2000. | Here are the figures for 1999-2000. Incorrect because a hyphen is used, which is too short. Here are the figures from 1999–2000. Incorrect because ‘from’ shouldn’t be used in conjunction with an en dash. |
| From 1898 to 1903. Between 1898 and 1903. | From 1898–1903. Incorrect because ‘from’ shouldn’t be used in conjunction with an en dash. From 1898-1903. Incorrect because a hyphen is used, which is too short. |
| From January 1, 1898 through December 31, 1903. Between January 1, 1898 and December 31, 1903. | From January 1, 1898–December 31, 1903. Incorrect because ‘from’ shouldn’t be used in conjunction with an en dash. From January 1, 1898-December 31, 1903. Incorrect because a hyphen is used, which is too short. |
| Between 150 and 200. | Between 150–200. Incorrect because ‘between’ shouldn’t be used in conjunction with an en dash. Between 150-200. Incorrect because a hyphen is used, which is too short. |
| Women aged forty-five to forty-nine years (hyphens). This example uses hyphens. | Women aged forty–five to forty–nine years. Incorrect because it uses an en dash for a compound word. Women aged forty–five–forty–nine years. Incorrect because a hyphen is used, which is too short. |
| Sixty- to seventy-year-olds (hyphens). This example uses hyphens. | Sixty– to seventy–year-olds. Incorrect because it uses an en dash for a suspended compound. Sixty-seventy-year-olds. Incorrect because it uses a hyphen to indicate a range. |
In the above table, the ‘Between 150–200’ and ‘Between 150-200’ examples are very common instances of en dash misuse. Here, the term ‘between’ defines the limits to the range of values. Therefore, we do not use an en dash to define the range.