Accuracy of Dexcom G4 vs G5

I just joined in hopes of getting some information about the accuracy of the Dexcom G4 vs G5. I am a long-term G4 user and have no complaints. I know the G5 transmits via Bluetooth, but that’s not especially important to me, and I like the long transmitter battery life of the G4.

But, someone told me that the G5 was significantly more accurate that the G4? My understanding is that the sensors are identical, so, presumably, if there’s a difference in accuracy, it is because the G5 uses a more updated algorithm to interpret the signal from the sensor?

I’d be happy to hear any thoughts.
Thanks much!

The algorithm used on the original G4 was updated. So, if you are using the new algorithm on the G4 then there is no difference between the G4 and the G5 in terms of accuracy. Exactly the same.

I believe the update was referred to as the “SW505” algorithm.

The update was applied to the G4 Dexcom Receiver.

My memory is consistent with @Tim35’s comment. The G4 with the updated 505 algorithm is the same accuracy as the G5 since it uses the same algorithm and sensor.

I, too, am holding back with the G4 system due to its longer transmitter life. I also like that the G4 has greater range between the transmitter and receiver.

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Thank you both! Your understanding confirms my own thinking.
I got the receiver I’m using now in January, 2018. Is there any way to be sure, or to check, that it has the new algorithm?

Your new G4 receiver delivered in January 2018 has the 505 update already installed. This update was published and made available since 2014. Here’s a partial screenshot of Dexcom’s announcement.

Thank you! Most helpful!!

So, I’m going to stick with the G4 for now.

I’m on Medicare and the G6 is not yet covered, as I understand it. But, do you have thoughts about whether and when to jump to the G6?

Thanks again!

The dexcom website says the g5 is accurate enough that you don’t need to do fingersticks for dosing. Well, I’m sorry but you do. My dexcom can be 1.5 to 2mmol off sometimes. It is accurate alot of the times but I find the inaccuracies are enough that it makes me not trust it as much. I can’t play around with my health that way!

You guys are referring to the G6. G6 is the high accuracy, no finger stick model. Oooops, didn’t realize how old this post was. It just popped up in my feed. I hate when that happens.