The plus or minus symbol (±) is a small sign with several important uses. You may see it in math equations, science lessons, measurements, statistics, and technical writing.
Many people search for this symbol because they want to know what ± means. Others want to learn how to type, copy, or use it correctly.
The symbol can mean two possible values in mathematics. It can also show an estimated amount or measurement uncertainty. Its meaning depends on the sentence or equation around it.
For example, x = ±5 means that x can be 5 or −5. But 10 ± 2 cm can describe a measurement from 8 to 12 cm.
This guide explains the plus or minus symbol in simple English. You will learn its meaning, uses, examples, pronunciation, and typing methods.
Plus or Minus Symbol (±) – Quick Answer
The plus or minus symbol is ±. It means “plus or minus” and can show two possible values or a range around a value. For example, x = ±5 means x = 5 or −5. In measurements, 10 ± 2 cm can mean a value from 8 to 12 cm.
What Does the Plus or Minus Symbol Mean?
The symbol ± combines two signs:
- + means plus.
- − means minus.
- ± means plus or minus.
The symbol can have different uses. Its exact meaning depends on the context.
Meaning in Math
In mathematics, ± often means that both signs are possible.
For example:
x = ±4
This gives two possible answers:
x = 4
or
x = −4
The symbol saves space. Instead of writing both answers separately, you can write them together.
Meaning in Measurements
The symbol can also show uncertainty or an expected range.
For example:
20 ± 3 cm
This can mean the measurement is centered around 20 cm. The stated variation is 3 cm.
The range would be:
17 cm to 23 cm
The exact interpretation depends on the measurement method and context.
Meaning in Estimates
The symbol can show that an amount may be higher or lower.
For example:
The repair may take 2 ± 0.5 hours.
This suggests an estimated time around two hours. The stated variation is half an hour.
For general readers, words such as “about” or “approximately” may be clearer.
How Is ± Used in Math?
The plus or minus symbol appears in many mathematical situations. One common use involves square roots and equations.
Consider:
x² = 25
The answers are:
x = 5
and
x = −5
Why are there two answers?
Because both values produce 25 when squared:
5 × 5 = 25
and
−5 × −5 = 25
Therefore, the answer can be written as:
x = ±5
This is one of the most common uses of the plus or minus symbol.
Using ± With a Number
A simple example is:
±7
This represents:
+7 or −7
The symbol tells you to consider both signs.
Using ± in the Quadratic Formula
The quadratic formula also uses the plus or minus symbol.
It gives two possible solutions when the expression under the square root allows them.
The symbol is useful because the formula contains both possible signs in one expression.
Using ± in Algebra
You may see expressions such as:
y = 8 ± 2
This means the two values are:
10 and 6
The plus version gives:
8 + 2 = 10
The minus version gives:
8 − 2 = 6
So, whenever you see ±, check whether the context requires both possibilities.
Plus or Minus Symbol Examples
Here are some simple examples.
1: Two Possible Answers
x = ±6
This means:
x = 6 or x = −6
2: A Measurement
Length = 15 ± 1 cm
This may represent a length from:
14 cm to 16 cm
3: An Estimate
Time = 30 ± 5 minutes
This can represent an estimated range from:
25 to 35 minutes
4: A Simple Expression
12 ± 4
The two results are:
16 and 8
5: Temperature
Temperature = 22 ± 2°C
The stated range is:
20°C to 24°C
Always consider the context before deciding what ± means.
Plus or Minus Symbol in Measurements
The plus or minus symbol is common in science and measurement.
For example:
50 ± 2 grams
The number 50 is the central value. The number 2 describes the stated uncertainty or variation.
This can represent a range from:
48 grams to 52 grams
However, ± does not always mean that every value in the range is equally likely. It simply shows the stated amount of variation or uncertainty unless the surrounding context says more.
This distinction matters in scientific writing.
For beginners, the easiest rule is:
Main value ± stated amount
For example:
100 ± 5
means the central value is 100. The stated amount is 5.
How to Type the Plus or Minus Symbol
The easiest method is often copying this symbol:
±
You can copy it directly from this article.
You may also insert the symbol through your device or software.
On Windows
Windows provides several ways to enter special characters. The exact method can depend on your keyboard, application, and settings.
In Microsoft Word, you can use Word’s symbol tools to insert ±.
In Microsoft Word
Open the Insert menu. Then choose the option for Symbol or More Symbols.
Find the plus-minus sign and insert it.
Word can also convert certain Unicode character codes into symbols. The plus-minus character has the Unicode code point U+00B1.
In Google Docs
In Google Docs, open the Insert menu. Choose Special characters.
Search for:
plus minus
Then select ± from the results.
On Mac
You can use the Mac keyboard’s special-character features to insert mathematical symbols. You can also use the character viewer to find ±.
In HTML
The plus or minus symbol can also be represented in HTML.
A common HTML entity is:
±
It displays as:
±
The Unicode code point is:
U+00B1
Plus or Minus Symbol vs Minus or Plus Symbol
The symbols ± and ∓ look similar. However, they are not the same.
| Symbol | Name | Basic Meaning |
| ± | Plus or minus | Plus or minus |
| ∓ | Minus or plus | Minus or plus |
The first symbol starts with plus.
The second symbol starts with minus.
You may see them together in advanced mathematical expressions.
For example, paired signs can show that one choice uses the plus sign while another uses the matching minus sign.
For beginners, remember this simple difference:
± = plus first
∓ = minus first
Plus or Minus Symbol vs Plus Sign
The plus sign + has one basic meaning. It usually represents addition or a positive value.
For example:
4 + 3 = 7
The plus or minus symbol ± has a different purpose.
For example:
x = ±3
This means:
x = 3 or x = −3
So, + and ± should not be treated as the same symbol.
How to Pronounce the Plus or Minus Symbol
The symbol ± is normally read as:
“plus or minus”
For example:
±5
can be read as:
“plus or minus five.”
You may also hear the shorter term:
“plus-minus.”
Both names refer to the same mathematical symbol.
The pronunciation is simple because the symbol directly represents the words.
Common Mistakes With the Plus or Minus Symbol
1: Writing +− Instead of ±
Incorrect:
x = +−5
Correct:
x = ±5
The standard plus or minus symbol is ±.
It combines the plus and minus signs into one character.
2: Thinking ± Always Means a Range
Incorrect idea:
x = ±5 always means every number from −5 to 5.
Correct idea:
x = ±5 means +5 or −5 in that mathematical context.
The symbol can represent a range in measurement contexts. Its meaning depends on how it is being used.
3: Using ± Without a Clear Context
Weak example:
The meeting takes ±30 minutes.
This is unclear because there is no central value.
Better example:
The meeting takes about 30 minutes.
Or:
The estimated time is 30 ± 5 minutes.
The second example gives a central estimate and stated variation.
4: Confusing ± With ∓
Incorrect idea:
± and ∓ are exactly the same.
Correct idea:
± means plus or minus.
∓ means minus or plus.
They can work together in some mathematical expressions, but they are different symbols.
Plus or Minus Symbol in Everyday Writing
The symbol can appear outside school math too.
In Emails
You might use ± when discussing an estimate.
For example:
The project may take 10 ± 2 days.
However, plain English may be easier for general readers:
The project may take about 10 days.
Choose the clearer option for your audience.
In News
News articles may use ± when reporting scientific measurements or technical findings.
For example:
The measured value was 25 ± 2 units.
News writers may spell out the meaning when readers need more explanation.
In Social Media
The symbol can appear in short posts, captions, and technical discussions.
For example:
Travel time: 2 ± 0.5 hours
A casual post may instead say:
Travel time: about two hours.
The best choice depends on your audience.
In Formal Writing
The symbol is common in scientific, mathematical, and technical writing.
For example:
The average result was 18 ± 3 units.
When writing for a general audience, explain the symbol if necessary.
Is Plus or Minus the Same in British and American English?
Yes.
The mathematical symbol ± is used in both British and American English.
There is no different British version and American version of the symbol.
You may see different wording around it, such as:
- plus or minus
- plus-minus
- plus or minus sign
- plus-minus sign
These expressions refer to the same basic symbol.
The symbol itself does not change.
Simple Rule to Remember
Use these three rules to remember ±:
- ± means “plus or minus.”
- In equations, it can show two possible values.
- In measurements, it can show stated variation or uncertainty.
Here is the easiest memory trick:
+ on top, − below, together they make ±.
If you see ±5, think:
“plus 5 or minus 5.”
If you see 10 ± 2, think:
“10, with 2 as the stated variation.”
FAQs
What is the plus or minus symbol?
The plus or minus symbol is ±. It combines the plus and minus signs into one mathematical character.
What does ± mean in math?
In math, ± often means that both the positive and negative versions apply. For example, x = ±4 means x = 4 or x = −4.
What does 10 ± 2 mean?
It means the central value is 10, with a stated variation of 2. In a simple range context, that gives values from 8 to 12.
How do I type the plus or minus symbol?
The easiest method is to copy ± directly. You can also insert it using symbol tools in programs such as Microsoft Word and Google Docs.
What is the Unicode for the plus or minus symbol?
The Unicode code point for the symbol ± is U+00B1. The symbol is known as the PLUS-MINUS SIGN.
What is the difference between ± and ∓?
± means “plus or minus,” while ∓ means “minus or plus.” They are separate symbols and can be used together in some mathematical expressions.
Is ± used in science?
Yes, the symbol is widely used in scientific and technical contexts. It can show measurement uncertainty, variation, or an estimated range.
Related Mathematical Symbols You Should Know
If you are learning mathematical symbols, these related topics can help:
- Plus Sign (+) — Used mainly for addition and positive values.
- Minus Sign (−) — Used mainly for subtraction and negative values.
- Minus-Plus Sign (∓) — The companion symbol to ±.
- Equal Sign (=) — Shows that two values or expressions are equal.
- Approximately Equal Sign (≈) — Shows that values are close but not exactly equal.
Learning these symbols together makes mathematical notation easier.
Conclusion
The plus or minus symbol (±) is used in math, science, measurements, and technical writing. Its basic meaning is “plus or minus.” In equations, it can show two possible values. For example, x = ±5 means x = 5 or x = −5.
The symbol can also show stated uncertainty or variation. For example, 10 ± 2 cm can represent a range from 8 to 12 cm in a simple measurement context.
The easiest way to remember it is simple: ± means plus or minus. You can copy the symbol directly when needed. Once you understand its context, reading and using ± becomes much easier.
