Difference between Single-mode and Multimode Fiber

Single-mode and multimode optical fibres are used in fibre optic communication systems. The diameter of the core, which impacts the number of light modes that can be broadcasted and the range over which the signal can be transferred, is the primary difference between the two.

Read this article to find out more about Single-Mode Fiber and Multimode Fiber and how they are different from each other.

What is Single-Mode Fiber?

SMF stands for single-mode fiber. It can transmit only one mode of light because of its small core diameter. Single-mode fibres are used in cable television and backbone networks. It is the best option for high-speed and data transmission over longer distances.

SMF transfers data up to 80 km at a speed of 100 gbps. Due to the small core diameter, it reduces signal attenuation and dispersion. SMF has the capacity to sustain signal integrity across long distances. SMF is frequently used in high- speed data transmission applications.

What is Multimode Fiber?

Multimode Fiber is also known as MMF. Multimode fiber can transfer the various light modes because its core diameter is larger; it is typically 50 or 62.5 microns. Multimode fiber is ideal for short-distance data transmission, such as within buildings or data centers, because it results in a lower bandwidth and shorter distances.

Multimode fiber allows the propagation of many modes of light, which can be generated by LED or laser light sources, due to the larger core size. In comparison to single-mode fiber, MMF fiber causes a higher level of modal dispersion, which restricts the bandwidth and range of the signal's transmission.

Multimode Fiber is commonly used in short-distance data transfer applications within buildings or data centers. It offers signal amplification-free data transfer across distances up to 550 metres at speeds up to 10 Gbps.

Multimode fiber is less expensive than single-mode fiber, because, for manufacturing, it requires less accuracy, which is one of its main advantages. It is more suitable for short-distance installations since it is also simpler to terminate and splice.

Multimode fiber is a popular optical fiber option for the transmission of short- distance, due to its affordability. Multimode fiber is the best choice for applications that don’t require high-speed or long-distance data transmission since it provides a less expensive option than single-mode fiber.

Difference between Single-Mode Fiber and Multimode Fiber

The following table highlights the major differences between Single-Mode Fiber and Multimode Fiber −


Single-Mode Fiber

Multimode Fiber

Diameter of a Core

It has a small diameter core

It has a large diameter core

Source Optical

SMF is a type of laser.

Multimode is LED.


The SMF bandwidth is more

The multimode fiber bandwidth is less


In telecom and CATV networks, SMF is preferred.

Multimode fibre is preferred in security systems and LANs.

Modal Dispersion

The single-mode fibre contains a narrower modal dispersion.

Multimode fibre has a wider range of modal dispersion.


It carries the signal with great speed

It transmits the signal slowly.


SMF is expensive.

Multimode fiber is low cost


The single-mode fibre wavelengths are 1310 nm and 1550 nm.

The multimode fibre wavelengths are 850 nm and 1300 nm.

Transmission Capactiy

SMF transmission capacity is less

Multimode fiber transmission capacity is more


The main difference between the two fibres is the size of the core, which affects the volume of light modes that can be transmitted and the transmission distance of the signal.

Single-mode fibre is used to transmit one mode of light. It has a low core diameter and offers the longest range for high speed. The data transmission can be done over a longer distance. Multimode fibre is used to transmit various modes of light. It has a larger core diameter and offers a shorter range with a lower bandwidth. Data transmission can be done for shorter distances.