Canon EOS Rebel T3i


Brand: Canon
Model: EOS Rebel T3i
Megapixels: 18.00
Sensor: 22.3 x 14.9 mm
Price: check here »

Sensor info

Canon Rebel T3i comes with a 22.3 x 14.9 mm CMOS sensor, which has a diagonal of 26.82 mm (1.06") and a surface area of 332.27 mm².
26.82 mm
Surface area
332.3 mm²
Pixel pitch
4.29 µm
Pixel area
18.4 µm²
Pixel density
5.43 MP/cm²
If you want to know about the accuracy of these numbers, click here.

Actual sensor size

Note: Actual size is set to screen → change »
This is the actual size of the Rebel T3i sensor: 22.3 x 14.9 mm
The sensor has a surface area of 332.3 mm². There are approx. 18,000,000 photosites (pixels) on this area. Pixel pitch, which is a measure of the distance between pixels, is 4.29 µm. Pixel pitch tells you the distance from the center of one pixel (photosite) to the center of the next.

Pixel or photosite area is 18.4 µm². The larger the photosite, the more light it can capture and the more information can be recorded.

Pixel density tells you how many million pixels fit or would fit in one square cm of the sensor. Canon Rebel T3i has a pixel density of 5.43 MP/cm².

These numbers are important in terms of assessing the overall quality of a digital camera. Generally, the bigger (and newer) the sensor, pixel pitch and photosite area, and the smaller the pixel density, the better the camera. If you want to see how Rebel T3i compares to other cameras, click here.


Brand: Canon
Model: EOS Rebel T3i
Also known as: EOS 600D, EOS Kiss X5 (Japan)
Effective megapixels: 18.00
Total megapixels: 18.70
Sensor size: 22.3 x 14.9 mm
Sensor type: CMOS
Sensor resolution: 5196 x 3464
Max. image resolution: 5184 x 3456
Crop factor: 1.61
Optical zoom:
Digital zoom: Yes
ISO: Auto, 100, 200, 400, 800, 1600, 3200, 6400, (12800 with boost)
RAW support:
Manual focus:
Normal focus range:
Macro focus range:
Focal length (35mm equiv.):
Aperture priority: Yes
Max aperture:
Max. aperture (35mm equiv.): n/a
Metering: Multi, Center-weighted, Spot, Partial
Exposure Compensation: ±5 EV (in 1/3 EV, 1/2 EV steps)
Shutter priority: Yes
Min. shutter speed: 30 sec
Max. shutter speed: 1/4000 sec
Built-in flash:
External flash:
Viewfinder: Optical
White balance presets: 6
Screen size: 3"
Screen resolution: 1,040,000 dots
Video capture:
Max. video resolution: 1920x1080 (30p/25p/24p)
Storage types: SDHC, SDXC, Secure Digital
USB: USB 2.0 (480 Mbit/sec)
Battery: Li-Ion
Weight: 570 g
Dimensions: 133.1 x 99.5 x 79.7 mm
Year: 2011

Compare Rebel T3i with another camera



Diagonal is calculated by the use of Pythagorean theorem:
Diagonal =  w² + h²
where w = sensor width and h = sensor height

Canon Rebel T3i diagonal:

w = 22.30 mm
h = 14.90 mm
Diagonal =  22.30² + 14.90²   = 26.82 mm

Surface area

Surface area is calculated by multiplying the width and the height of a sensor.

Width = 22.30 mm
Height = 14.90 mm

Surface area = 22.30 × 14.90 = 332.27 mm²

Pixel pitch

Pixel pitch is the distance from the center of one pixel to the center of the next measured in micrometers (µm). It can be calculated with the following formula:
Pixel pitch =   sensor width in mm  × 1000
sensor resolution width in pixels

Canon Rebel T3i pixel pitch:

Sensor width = 22.30 mm
Sensor resolution width = 5196 pixels
Pixel pitch =   22.30  × 1000  = 4.29 µm

Pixel area

The area of one pixel can be calculated by simply squaring the pixel pitch:
Pixel area = pixel pitch²

You could also divide sensor surface area with effective megapixels:
Pixel area =   sensor surface area in mm²
effective megapixels

Canon Rebel T3i pixel area:

Pixel pitch = 4.29 µm

Pixel area = 4.29² = 18.4 µm²

Pixel density

Pixel density can be calculated with the following formula:
Pixel density =  ( sensor resolution width in pixels )² / 1000000
sensor width in cm

You could also use this formula:
Pixel density =   effective megapixels × 1000000  / 10000
sensor surface area in mm²

Canon Rebel T3i pixel density:

Sensor resolution width = 5196 pixels
Sensor width = 2.23 cm

Pixel density = (5196 / 2.23)² / 1000000 = 5.43 MP/cm²

Sensor resolution

Sensor resolution is calculated from sensor size and effective megapixels. It's slightly higher than maximum (not interpolated) image resolution which is usually stated on camera specifications. Sensor resolution is used in pixel pitch, pixel area, and pixel density formula. For sake of simplicity, we're going to calculate it in 3 stages.

1. First we need to find the ratio between horizontal and vertical length by dividing the former with the latter (aspect ratio). It's usually 1.33 (4:3) or 1.5 (3:2), but not always.

2. With the ratio (r) known we can calculate the X from the formula below, where X is a vertical number of pixels:
(X × r) × X = effective megapixels × 1000000    →   
X =  effective megapixels × 1000000
3. To get sensor resolution we then multiply X with the corresponding ratio:

Resolution horizontal: X × r
Resolution vertical: X

Canon EOS Rebel T3i sensor resolution:

Sensor width = 22.30 mm
Sensor height = 14.90 mm
Effective megapixels = 18.00
r = 22.30/14.90 = 1.5
X =  18.00 × 1000000  = 3464
Resolution horizontal: X × r = 3464 × 1.5 = 5196
Resolution vertical: X = 3464

Sensor resolution = 5196 x 3464

Crop factor

Crop factor or focal length multiplier is calculated by dividing the diagonal of 35 mm film (43.27 mm) with the diagonal of the sensor.
Crop factor =   43.27 mm
sensor diagonal in mm

Canon Rebel T3i crop factor:

Sensor diagonal = 26.82 mm
Crop factor =   43.27  = 1.61

35 mm equivalent aperture

Equivalent aperture (in 135 film terms) is calculated by multiplying lens aperture with crop factor (a.k.a. focal length multiplier).

Canon EOS Rebel T3i equivalent aperture:

Aperture is a lens characteristic, so it's calculated only for fixed lens cameras. If you want to know the equivalent aperture for Canon EOS Rebel T3i, take the aperture of the lens you're using and multiply it with crop factor.

Crop factor for Canon Rebel T3i is 1.61

Enter your screen size (diagonal)

My screen size is  inches

Actual size is currently adjusted to screen.

If your screen (phone, tablet, or monitor) is not in diagonal, then the actual size of a sensor won't be shown correctly.