Percentage to PX Converter
Convert relative percentage values to absolute pixel measurements
Percentage to PX Calculator
Percentages in CSS are always relative to another value. For width/height, they're relative to the parent container's dimensions. To convert percentage to pixels, you need to multiply the percentage by the reference size.
Conversion Result
Visual Representation
See how this percentage looks visually:
Common Grid Layouts
Examples of common grid column widths:
Batch Converter
Convert multiple percentage values at once. Enter values separated by spaces, commas, or new lines.
Batch Results
| Percentage | Pixels | CSS Code |
|---|
Common Percentage to PX Conversions
Based on different container sizes, here are common percentage conversions:
| Percentage | 320px Mobile | 768px Tablet | 1024px Laptop | 1440px Desktop |
|---|---|---|---|---|
| 100% | 320px | 768px | 1024px | 1440px |
| 75% | 240px | 576px | 768px | 1080px |
| 50% | 160px | 384px | 512px | 720px |
| 33.33% | 107px | 256px | 341px | 480px |
| 25% | 80px | 192px | 256px | 360px |
| 20% | 64px | 154px | 205px | 288px |
| 10% | 32px | 77px | 102px | 144px |
Frequently Asked Questions
In CSS, percentage values are always relative to another value, but what they're relative to depends on the property:
- Width - Relative to the parent element's width
- Height - Relative to the parent element's height
- Margin and Padding - Always relative to the parent element's width (even for top/bottom margins and padding)
- Font Size - Relative to the parent element's font size
- Top/Bottom - Relative to the parent's height
- Left/Right - Relative to the parent's width
- Transform: translate - Relative to the element itself (translateX to its width, translateY to its height)
It's important to remember that for padding and margin, percentages are always calculated based on the parent element's width, even for top and bottom padding/margins.
Percentage units are particularly useful in the following scenarios:
- Responsive Layouts - Creating layouts that adapt to different screen sizes by scaling proportionally with the container size.
- Fluid Grids - Building grid systems where columns take up a percentage of the available space.
- Maintaining Aspect Ratios - Using the padding trick (padding-bottom with percentage) to maintain aspect ratios for responsive elements.
- Equal Spacing - Creating evenly spaced elements that maintain their proportions as the screen size changes.
- Flexible Images - Making images scale with their container while maintaining proportions.
Fixed units like pixels are generally better for:
- Borders and small UI elements
- Typography (although rem is often preferred)
- Elements that should not scale with their container
- When you need precise control at specific sizes
Modern responsive design often combines percentage-based layouts with relative units (like rem) for typography and min/max constraints for controlled flexibility.
To calculate pixel values from percentages manually, use this formula:
For example, if your container width is 1200px:
- 100% = (100 / 100) x 1200px = 1200px
- 50% = (50 / 100) x 1200px = 600px
- 33.33% = (33.33 / 100) x 1200px = 400px
- 25% = (25 / 100) x 1200px = 300px
- 10% = (10 / 100) x 1200px = 120px
For common grid layouts, you can use these standard percentage values:
- Half width: 50%
- Third width: 33.33%
- Quarter width: 25%
- Fifth width: 20%
- Sixth width: 16.67%
- Eighth width: 12.5%
- Tenth width: 10%
- Twelfth width: 8.33%
Pros of Percentage-Based Layouts:
- Responsiveness - Elements scale proportionally with viewport or container size.
- Flexibility - Works across different screen sizes without multiple breakpoints.
- Proportional Relationships - Maintains consistent ratios between elements.
- Easier Maintenance - Fewer hard-coded values to update when making layout changes.
- Fluid Layout - Creates a more natural, flowing design that adapts smoothly.
Cons of Percentage-Based Layouts:
- Limited Control - Less precise control over exact dimensions at specific sizes.
- Dependency on Parent - Changes to parent size can affect all child elements unexpectedly.
- Potential for Extreme Sizes - Elements can become too small on small screens or too large on big screens.
- Complexity with Nested Elements - Calculating nested percentages can be confusing.
- Content Constraints - May not account for the actual content size needs.
Best practice: Combine percentage-based layouts with min/max width/height constraints to ensure elements remain usable across all screen sizes.
/* Example of best practice */
.responsive-element {
width: 50%; /* Percentage-based width */
min-width: 300px; /* Minimum width constraint */
max-width: 600px; /* Maximum width constraint */
}
About Percentage Units
Percentage units in CSS express a size relative to another value, making them essential for creating fluid, responsive layouts that adapt to different screen sizes.
Key Points About Percentages
-
Relativity: Always relative to another value
-
Responsiveness: Scales with parent container dimensions
-
Fluidity: Creates smooth scaling across different devices
-
Proportionality: Maintains consistent ratios in layouts
Percentage units have been part of CSS since the beginning and are supported in all browsers, making them a reliable choice for responsive design.
CSS Usage Examples
Common ways percentage units are used in CSS:
/* Responsive container */
.container {
width: 90%;
max-width: 1200px;
margin: 0 auto;
}
/* Simple grid system */
.row {
display: flex;
flex-wrap: wrap;
}
.col-half {
width: 50%;
}
.col-third {
width: 33.33%;
}
.col-quarter {
width: 25%;
}
/* Responsive images */
img {
max-width: 100%;
height: auto;
}
/* Aspect ratio box (16:9) */
.video-container {
position: relative;
width: 100%;
height: 0;
padding-bottom: 56.25%; /* 9/16 = 0.5625 */
}
.video-container iframe {
position: absolute;
width: 100%;
height: 100%;
top: 0;
left: 0;
}
/* Padding that scales with width */
.card {
padding: 5%;
margin-bottom: 5%;
}For grid layouts, remember to account for gutters by slightly reducing column widths if you need spacing between columns.