This article gives a brief description of the difference between SIM900 and SIM800 GSM modules. SIM800 modules are upgraded version of its previous successful GSM/GPRS/GPRS module series SIM900. There are multiple sub versions of each series, each of which cater to a different set of users and applications.

SIM800 vs SIM900 GSM modules

There exist multiple versions of these modules, 

SIM900 comes in the form of full version Quad band SIM900 & dual band version SIM900A, SIM900D 

SIM800 comes in the form of full version Quad band SIM800 & stripped down compact size version SIM800C. 

There are other SIM800 & SIM900 versions but very less information available about them, so they have not been discussed.

Since we are already very familiar with interfacing the SIM900 modem and have played around with the AT commands, the questions that come to our mind are listed below. I have tried to answer them after doing a bit web research.


"What extra does SIM800 modules give me compared to SIM900 series modules?" 

SIM800 GSM modules have a inbuilt Bluetooth stack compliant with 3.0+EDR & FM radio support, and the interface is accessible using AT commands.

SIM800C GSM module is comes in a very compact size of 17.6*15.7*2.3 mm dimensions compared to SIM900/SIM900 which come in 24*24*3mm package.


"How compatible are these both modem series?" 

SIM800,SIM800C modem operates from 3.4V to 4.4V supply range (Reduced operating range  !)

SIM900, SIM900A modules operate from 3.2V to 4.8V supply range. 

Same AT commands used for simple call/sms functionality in SIM900,SIM900A can be used with the SIM800,SIM800C modules, but SIM800 series have added AT command set for supporting extra features like bluetooth.


"Which module should i use?"

First thing is you should use SIM800 module only if you need the features that are not present in SIM900 series modules, like ,

Use SIM800 module if you need Bluetooth/FM functionality which was missing in SIM900 series.

Use SIM800C module if you have stringent size constraints, SIM800C is almost a centimeter smaller in size compared to SIM800 module and it is a huge saving on PCB real estate. 

SIM800, SIM800C, SIM900 can be operated worldwide because they can operate in all four GSM bands used across the world. 


"What is the price difference?"

SIM900 is available for purchase @ Rs. 800 /- 

SIM900A is available for purchase @ Rs. 600 /- 

SIM800 is available for purchase @ Rs.700/-

SIM800C is available for purchase @ Rs.500 /-


"Where can i buy these modules?"

For large volume purchases it is better to buy these parts from or

If you are from India, read the post, Where to buy electronics components in India?  for more information.

Use this search engine to find electronics components quickly, Click Here,


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About the Author

is the author of this blog and is an Embedded systems design engineer by profession & Founder @ Valetron Systems Pvt Ltd

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