If you searched for “minus plus sign”, you are looking for an explanation of two of the most familiar symbols in mathematics and everyday life: the minus sign, written as a short horizontal line, and the plus sign, written as a cross. Together, they appear in school maths, in weather forecasts, in sports tables, in product specifications, and in scientific measurements. This guide explains what each sign means on its own, what happens when they are combined into the plus-minus symbol, and how to read them confidently wherever you meet them.
Plus and minus are among the first symbols children learn, but their uses grow more sophisticated with age. A plus sign can mean addition, a positive value, or an advantage. A minus sign can mean subtraction, a negative value, or a shortfall. Combined, the two signs form a symbol that expresses uncertainty, tolerance, or a range of possible values. Learning to tell those meanings apart is a small skill that pays off every day, from checking a bank balance to reading a forecast.
Minus Plus Sign Basics: Plus and Minus on Their Own
Start with the minus plus sign pair in their simplest form. The plus sign means add, or more. In the sum 4 + 3 = 7, the plus sign tells you to combine four and three to make seven. In everyday language, the same idea appears in phrases such as “plus tax” or “three plus”, where plus signals something extra on top of a stated figure. A plus sign in front of a number, as in +5, marks it as positive, meaning greater than zero.
The minus sign means subtract, or less. In the sum 9 − 4 = 5, the minus sign tells you to take four away from nine, leaving five. In front of a number, as in −5, it marks the number as negative, meaning less than zero. Negative numbers describe things like temperatures below freezing, depths below sea level, or an account that is overdrawn. The minus sign in −5 is not an instruction to subtract; it is part of the number itself, telling you which side of zero it sits on.
That distinction matters. In the expression 7 − 3, the minus sign is an operation, an instruction to subtract. In the temperature −3 degrees, the minus sign is a sign, telling you the temperature is three degrees below zero. The same symbol does both jobs, and context tells you which one is meant. Once you see that, many confusing-looking expressions become much clearer.
Minus Plus Sign Combined: The Plus-Minus Symbol
When the minus plus sign pair is combined into a single symbol, written with a plus sign over a minus sign, it is called the plus-minus symbol. It is used to express a value together with its uncertainty or its acceptable range. For example, a measurement written as 20 ± 2 means the true value is expected to lie somewhere between 18 and 22. The central figure is the best estimate, and the figure after the symbol is the margin on either side.
Scientists and engineers use the plus-minus symbol constantly, because no measurement is perfectly exact. A length, a weight, a temperature, or a survey result always carries some uncertainty, and honest reporting shows that uncertainty rather than hiding it. A poll result reported as 48 per cent, plus or minus 3 points, is telling you that the true figure is probably between 45 and 51 per cent. Without the margin, the single number would look far more precise than it really is.
In manufacturing, the plus-minus symbol expresses tolerance: how much a part may vary from its intended size and still be acceptable. A bolt specified as 10 millimetres, plus or minus 0.1 millimetres, must measure between 9.9 and 10.1 millimetres to pass inspection. Anything outside that range is rejected, because it may not fit or function correctly. Tolerance is what makes mass production possible: parts made in different factories, on different days, can still fit together if each one stays within its stated tolerance.
There is also a reversed form, the minus-plus symbol, with the minus sign on top. It is much rarer, and it appears mainly in advanced mathematics, where it is used alongside the plus-minus symbol to show two linked values that vary in opposite directions. Most readers will never need it, but knowing it exists can prevent confusion if you ever meet it in a technical document. For a related idea in school mathematics, see our guide to the converse in mathematics.
Minus Plus Sign in Everyday Life
Outside the classroom, plus and minus signs appear in many familiar places. Weather forecasts use minus for temperatures below zero and plus, or no sign at all, for temperatures above zero. A forecast of minus 2 degrees means two degrees below freezing, so you should expect frost, while a forecast of plus 2 degrees means two degrees above freezing. In countries that use Fahrenheit, the same logic applies: minus figures are below zero on that scale.
Sports tables use plus and minus to show goal difference, the difference between goals scored and goals conceded. A team that has scored 30 goals and conceded 20 has a goal difference of plus 10, while a team that has scored 20 and conceded 30 has a goal difference of minus 10. Goal difference is often used to separate teams that finish level on points, so a single goal can change a team’s position in the table. The same idea appears in other sports with points difference or run difference.
In finance, plus and minus show profit and loss, growth and decline. A bank balance with a plus sign, or no sign, is in credit. A balance with a minus sign is overdrawn, meaning more has been spent than was available. A share price that rises is shown with a plus, and one that falls is shown with a minus. Reading those signs correctly is essential, because the same number means the opposite thing depending on which sign it carries.
Batteries, chargers, and electrical equipment use plus and minus to mark terminals. The plus terminal is positive and the minus terminal is negative, and connecting them the right way round matters: a battery inserted backwards will not power a device, and in some equipment it can cause damage. The symbols are usually moulded into the battery compartment, so check them before you press a battery into place.
Plus and Minus Meanings at a Glance
| Where you see it | What it means | Example |
|---|---|---|
| Arithmetic | Add or subtract | 4 + 3 = 7; 9 − 4 = 5 |
| Positive and negative numbers | Above or below zero | +5 is positive; −5 is negative |
| Plus-minus symbol | A value with an uncertainty or range | 20 ± 2 means between 18 and 22 |
| Weather | Above or below freezing | −2 degrees means two below zero |
| Sport | Goal or points difference | Plus 10 means ten more scored than conceded |
| Finance | Credit or debit, gain or loss | Minus balance means overdrawn |
| Batteries | Positive and negative terminals | Plus to plus, minus to minus |
Minus Plus Sign Rules in School Maths
A few simple rules govern how plus and minus signs combine in school mathematics, and learning them removes a lot of confusion. When you add a positive number, you move up the number line. When you add a negative number, you move down, which is the same as subtracting. When you subtract a negative number, you move up, because taking away a negative is the same as adding a positive. That is why 5 − (−3) equals 8: subtracting minus three is the same as adding three.
Multiplication and division follow a similar pattern. A positive multiplied by a positive gives a positive. A positive multiplied by a negative gives a negative. A negative multiplied by a negative gives a positive. The same rules apply to division. A useful way to remember this is that two like signs give a positive result, while two unlike signs give a negative result. Practising with a number line makes these rules intuitive: you can see the movement left or right for each operation, rather than memorising rules blindly.
Students often stumble when a minus sign appears in front of a bracket, as in −(3 + 2). The minus sign outside the bracket changes the sign of everything inside it, so −(3 + 2) equals −5. Similarly, a minus sign in front of a letter, as in −x, means the negative of whatever value x holds, not necessarily a negative number: if x itself is negative, then −x is positive. Keeping the distinction between a sign and an operation clear will carry you through algebra, and into the equations of science, where the same symbols appear. For another building block of scientific language, see our guide to the dependent variable.
Typing and Writing Plus and Minus Signs
Typing these symbols is straightforward on most devices, but a few details are worth knowing. The plus sign is on every keyboard, usually near the top row or the number pad. The minus sign used for subtraction is the hyphen key on most keyboards, although typography distinguishes a short hyphen from a slightly longer minus sign. For everyday writing, the hyphen key is perfectly acceptable, and most readers will understand it as a minus sign.
The plus-minus symbol is less accessible. On a computer, it can be inserted from a character map or symbols menu, or typed with a keyboard shortcut that varies by operating system. On a phone, it is usually found by long-pressing a related key or by opening the symbols keyboard. If you cannot insert the symbol easily, writing “plus or minus” in words is clear and correct, and it is often better than using a symbol your reader’s device may not display properly.
Handwriting deserves a note too. Write the minus sign as a clear horizontal line, and the plus sign as two lines crossing at right angles, with the vertical line slightly longer than the horizontal one. In rushed handwriting, a plus sign can look like a letter t, and a minus sign can look like a dash or an underline, so take a moment to make them distinct. Clear symbols prevent marking errors in exams and misunderstandings in notes.
Frequently Asked Questions
What does the plus-minus symbol mean?
It means a value plus or minus a stated amount. A figure written as 20 ± 2 means the value is expected to fall between 18 and 22, with 20 as the central estimate.
Is a minus sign the same as a negative number?
Not always. A minus sign can be an instruction to subtract, as in 9 − 4, or it can be part of a number, marking it as negative, as in −5. Context tells you which role it is playing.
What does a plus sign in front of a number mean?
It marks the number as positive, meaning greater than zero. In many contexts, positive numbers are written without any sign at all, so an explicit plus sign is used mainly for emphasis or contrast with negative figures.
Why do two minuses make a plus?
Because subtracting a negative number is the same as adding a positive one. On a number line, subtracting a negative moves you in the positive direction, so 5 − (−3) equals 8.
Conclusion
The minus plus sign pair is small, but it carries a remarkable range of meanings, from simple addition and subtraction to measurement uncertainty, manufacturing tolerance, weather, sport, finance, and electrical polarity. The key to reading these symbols is context: ask whether the sign is an instruction, part of a number, or part of a range, and the meaning usually becomes clear. The plus-minus symbol deserves special attention, because it is the honest way to report a measurement or a result that is not perfectly exact. Once you can read plus, minus, and plus-minus with confidence, you will find that a great many tables, forecasts, specifications, and school problems become noticeably easier to understand.
