2.5 rem equals 40 pixels.
Table of Contents
The conversion from rem to pixels depends on the root font size of the webpage. By default, most browsers set the root font size to 16 pixels. Therefore, multiplying 2.5 rem by 16 pixels gives the equivalent pixel value.
Conversion Tool
Result in pixel:
Conversion Formula
The conversion formula is: pixels = rem × root font size.
Since the root font size is usually 16 pixels (the browser default), each rem unit is 16 pixels. To convert 2.5 rem to pixels, multiply 2.5 by 16.
Step-by-step:
- Start with the rem value: 2.5
- Multiply by root font size: 2.5 × 16
- Resulting pixel value: 40 pixels
This works because rem units are relative to the root element’s font size, which controls the base size for scaling.
Conversion Example
- 1.2 rem to pixels:
- Take rem value: 1.2
- Multiply by 16: 1.2 × 16 = 19.2 pixels
- So, 1.2 rem equals 19.2 pixels.
- 0.75 rem to pixels:
- Multiply 0.75 × 16
- Result: 12 pixels
- Therefore, 0.75 rem equals 12 pixels.
- 3 rem to pixels:
- Multiply 3 × 16 = 48 pixels
- 3 rem corresponds to 48 pixels.
- 5 rem to pixels:
- 5 × 16 = 80 pixels
- Thus, 5 rem is 80 pixels.
- 0 rem to pixels:
- 0 × 16 = 0 pixels
- Zero rem is zero pixels.
Conversion Chart
| Rem | Pixels |
|---|---|
| -22.5 | -360 |
| -20.0 | -320 |
| -17.5 | -280 |
| -15.0 | -240 |
| -12.5 | -200 |
| -10.0 | -160 |
| -7.5 | -120 |
| -5.0 | -80 |
| -2.5 | -40 |
| 0.0 | 0 |
| 2.5 | 40 |
| 5.0 | 80 |
| 7.5 | 120 |
| 10.0 | 160 |
| 12.5 | 200 |
| 15.0 | 240 |
| 17.5 | 280 |
| 20.0 | 320 |
| 22.5 | 360 |
| 25.0 | 400 |
| 27.5 | 440 |
The chart shows rem values in the first column and their equivalent pixel values in the second. You can find the rem number you want and see the corresponding pixels, which helps quickly estimate sizes without calculation.
Related Conversion Questions
- How many pixels is 2.5 rem when the root font size changes?
- What is the pixel value of 2.5 rem on a website with 18px base font?
- Does 2.5 rem always equal 40 pixels or can it vary?
- How do I convert 2.5 rem to pixels in CSS?
- Why does 2.5 rem sometimes look bigger than 40 pixels on some browsers?
- What happens to 2.5 rem if the root font size is set to 20px?
- Is 2.5 rem equal to the same pixels on mobile and desktop?
Conversion Definitions
rem: A CSS unit that represents the font size of the root element (usually the <html> tag). Unlike em units, rem is consistent across the document because it always refers to the root font size, allowing for scalable, relative sizing that adjusts if the root font size changes.
pixel: The smallest unit of measurement on a screen, representing a single point of color. Pixels form the building blocks of digital images and screen displays, with sizes depending on screen resolution and density, making them an absolute unit used for precise layout control.
Conversion FAQs
Can the value of 2.5 rem in pixels change between browsers?
Yes, if the root font size differs in browsers or user settings. Since rem calculates relative to the root font size, any changes to it will affect the pixel equivalent. However, most browsers default to 16px unless customized.
What if the root font size is not 16 pixels, how to convert 2.5 rem then?
Multiply 2.5 by the actual root font size set on the page. For example, if root font size is 18px, then 2.5 rem equals 2.5 × 18 = 45 pixels. Always check the root font size to get accurate pixel values.
Why is rem preferred over pixels in responsive design?
rem units scale with the root font size, allowing designs to adapt when users change font size preferences or when different devices have varying base sizes. Pixels are fixed and don’t scale, which can cause layout issues on accessibility or zoom.
Does changing the root font size affect all rem values including 2.5 rem?
Yes, changing the root font size rescales all rem values proportionally. So if root font size increases, 2.5 rem becomes larger in pixels, making the page elements bigger accordingly.
Can negative rem values like -2.5 rem be used in CSS, and what does it mean in pixels?
Negative rem values are valid in CSS for properties that accept negative lengths, like margins. For -2.5 rem, multiply by root font size, so -2.5 × 16 = -40 pixels, meaning a negative offset or shrinkage by 40 pixels.