The short answer is the higher the resolution, the better. If you have a 2MP (1080p) camera, zooming in will not reveal any extra detail. Hence if you want to zoom in on faces and number plates while preserving the quality of the footage, having a higher-resolution camera is a must.
We compare 720p vs. 1080p vs. Vs. 4k vs. 4MP vs. 5MP below.
Many security cameras that claim high resolution still cannot capture good-quality pictures or videos. Pictures and videos taken by these are often blurry; you can’t even identify an intruder’s face or read license plates.
This makes you wonder, “What is the best resolution for a security camera? Well, the TLDR answer is the higher the resolution, the better. But there is more to the resolution than this.
What Is Security Camera Resolution?
Security camera resolution is the total number of pixels present in a sensor of the security camera. Accordingly, the resolution of a security camera also determines the number of pixels in the image.
The resolution of security cameras is usually measured in megapixels. One megapixel is equal to one million pixels. The resolution of images, however, is usually measured as a spatial resolution which is the height and width of the picture measured in pixels.
For example, a camera with 2 megapixels (MP) resolution captures images that have 2MP resolution. These images have dimensions of 1920 x 1080. These numbers give the number of rows and columns of pixels in the image. An image captured by a 2MP camera has 1920 rows of pixels horizontally and 1080 columns of pixels vertically.
Multiplying these two numbers, you get the total number of pixels which is exactly 2,073,600 pixels. Spatial resolution is usually identified by the number of pixel rows (picture height), and the number of pixel columns (picture width) is implied and fixed for each resolution. A 2MP image can be said to have a resolution of 1080p.
For security cameras, the most common resolutions are 2MP, 4MP, 5MP, and 8MP. These security cameras capture footage with resolutions of 1080p, 1440p, 1920p, and 2160p (4K), respectively.
Security Camera Resolution Comparison Chart
The following chart compares security camera resolutions, image sizes, and aspect ratios.
| Camera Resolution | Spatial Resolution | Number of Pixels | Aspect Ratio |
| 2MP | 1920 × 1080 | 2,073,600 | 16:9 |
| 4MP | 2560 × 1440 | 3,686,400 | 16:9 |
| 5MP | 2560 × 1920 | 5,017,600 | 4:3 |
| 8MP (4K) | 3840 × 2160 | 8,294,400 | 16:9 |
720p vs 1080p vs Vs 4k vs 4MP vs 5MP: Which to Choose
In every case, a higher-resolution security camera is better than a lower-resolution security camera. But some nuanced differences make 4K security cameras better than others.
Image Quality
More pixels mean better resolution. An image or video captured by a high-resolution security camera is more detailed and has more information. This allows you to identify faces and read license plates at a distance.
You might be wondering, “4K? Who has a 4K security monitor?” True, no one view security footage on a 4K smart TV. But the primary purpose of this high resolution is to enable you to zoom in or enlarge recorded footage. Zooming in on low-resolution footage does not reveal any more information. It lowers the quality, and you are still unable to see what you want to see. However, a 4K security camera allows you to zoom in without losing quality. (1)
Live Stream Resolution
You can stream footage from a high-resolution security camera on a low-resolution screen. Live footage from a 4K security camera can be viewed on a 4K screen, a 1920p screen, a 1440p screen, a 1080p screen, and so on. Any high-resolution footage can be viewed on a low-resolution screen. If you have a high-resolution camera, you can zoom in on different areas in real-time and still view high-resolution footage.
One big issue, though, to keep in mind is that because of the large data transfer size, if you use a wifi camera, these higher resolutions may cause lag to occur if your internet cannot support them.
Field of View
As you can see in the picture, a 5MP camera has more pixels than a 4MP camera but only vertically. There is no gain in horizontal resolution. However, for most security cameras, horizontal coverage is more important than vertical coverage. Hence, the extra resolution of a 5MP camera is not useful in many cases.
As shown in the resolution chart, 4MP cameras are 3.6MP but are advertised as 4MP. Lower resolution limits how much you can zoom in before the quality declines. If you have a 2MP camera and your monitor is 1080p, there is no point in zooming. The camera does not have any more detail to offer.
4K security cameras are 8MP. Horizontally, this resolution of a 4K camera is two times higher than both 5MP and 4MP security cameras, allowing you to zoom twice as much and view twice as clearly. The resolution of a 4K camera is also four times higher than a 2MP camera.
Bandwidth & Storage Consumption
Higher-resolution cameras deliver higher-resolution footage which is composed of more information. A higher-resolution camera will require higher bandwidth and more storage space.
What situation is each resolution best for
Having a high-resolution camera can never do you any harm. Hence, a 4K security camera is ideal for every situation. But practically, there are some situations where you do not need a high-resolution camera. For instance, if you wish to place a camera to view general movement and do not need much detail, a 2MP camera would work for you.
If you need high-quality footage but want the footage to have a higher resolution vertically (you want more vertical coverage), a 5MP camera will deliver footage almost as detailed as a 4K camera.
4MP and 5MP cameras will work if you need moderately detailed footage. However, remember that 4MP is just 3.6MP, and 5MP does not deliver any better horizontal resolution than 4MP.
Analog Security Camera Resolution
Analog cameras send data differently than digital cameras. Since these cameras are derived from old CRT analog TV technology, the resolutions of these cameras tend to be significantly lower than digital cameras. (2)
Analog Security Camera Resolution Comparison Chart
Here is a chart giving the resolutions of different analog security cameras.
| Camera Resolution | Image Resolution |
| QCIF | 176 × 120 |
| CIF | 352 × 240 |
| D1 or 4CIF | 704 × 480 |
| 960H | 960 × 480 |
| 720p AHD | 1280 × 720 (720p) |
| 1080p AHD | 1920 × 1080 (1080p) |
High-resolution security cameras are better than lower-resolution alternatives. They deliver more detailed footage, which allows you to zoom in real-time, even in recorded footage, without dropping the quality of the footage. 4K security cameras stand out as the best choice because of their significantly higher resolution and aspect ratio, which is suitable for security cameras.
References
(1) Zooming in – https://photographylife.com/what-is-zoom-in-photography
(2) analog – https://www.britannica.com/technology/analog-signal