What GNSS accuracy values are you seeing?

Discussion related to the Garmin GPSMAP H1 series GPSr
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JungleJim
Posts: 540
Joined: Sat Mar 05, 2022 3:45 pm
Location: Netherlands

What GNSS accuracy values are you seeing?

Post by JungleJim »

Now that the H1i / H1i Plus have been out for 9 months, and the device having received multiple firmware updates, including updates of the GPS firmware, I'm wondering what kind of accuracy numbers others are seeing?

Coming from a GPSMAP 66sr and GPSMAP 67 (as most recent GPSMAP devices), I notice that both devices consistently displayed an accuracy of 1.8m in good conditions and with multi-GNSS and multi-band.

With my H1, not so much.

I usually have my device on Auto Select. When it's in multi-GNSS mode without multi-band, I get 3.0m as the best accuracy. The device receives satellites from GPS, Galileo and BeiDou, with around 10 satellites. Usually BeiDou has a bit more than the other two systems. And I noticed that with 10.13, there's no GLONASS reception.

When the device uses multi-GNSS with multi-band, I usually get no better than 2.3m but mostly 2.4m - 2.5m in my local test walk (in a neighborhood with low-rise housing, and some open areas, around latitude N52 and longitude E05).

So what are the experiences of other H1 / H1i users?
Current: GPSMAP H1, inReach Mini 2 - Previous: GPSMAP 67, inReach Messenger, GPSMAP 66sr, Oregon 700, Dakota 20, Edge 1040, Edge 1030 Plus, Edge 1030, Edge 520 Plus, Edge 520
NellieD
Posts: 1
Joined: Tue Oct 14, 2025 8:34 am

Re: What GNSS accuracy values are you seeing?

Post by NellieD »

I have all systems and multiband enabled. I live in Scheveningen (N52 E004). I can see GPS, Galileo, and BeiDou, but no longer GLONASS. At the beach near the Zandmotor, I had 1.9-meter accuracy—which is a very open area by Dutch standards. If I go to Scheveningen beach, it’s 2.3.
Dutch
Bij staan alle systemen plus multiband aan. Ik woon in Scheveningen N52 O004 . Ik zie GPS, Galileo en Beidou, Glonass dus niet meer. Op het strand bij Zandmotor had ik een ontvanst van 1,9 meter, dat is wel een zeer open gebied voor Nederlandse begrippen. Ga ik naar het strand van Scheveningen dan is het 2.3.
MaartenD Scheveningen
JungleJim
Posts: 540
Joined: Sat Mar 05, 2022 3:45 pm
Location: Netherlands

Re: What GNSS accuracy values are you seeing?

Post by JungleJim »

Dank voor je reactie 😀

I haven’t seen 1.9m myself but good to know the device is capable of that accuracy!
Current: GPSMAP H1, inReach Mini 2 - Previous: GPSMAP 67, inReach Messenger, GPSMAP 66sr, Oregon 700, Dakota 20, Edge 1040, Edge 1030 Plus, Edge 1030, Edge 520 Plus, Edge 520
kwieto
Posts: 4
Joined: Fri May 29, 2026 8:00 am

Re: What GNSS accuracy values are you seeing?

Post by kwieto »

I wouldn't look that match for comparing the values showed on the satellite view.
They don't show you how accurate the readinds are, but rather how "precise" position readings are (it is not the same).
You may compare that to the two thermometers, one has a scale by 1 degree, the other by 0.1 degree. But the first one is very precise (so if it say 20 degrees you may be sure that it is exactly 20 degrees), the second not so (so if it shows 20.3 degrees, in fact it might be either 18.3, 22.3 or something in between).
It looks like the second one is better (it shows the values with the precision of 0.1 degree), but in fact it may be much more off the real value than the first one.
The same goes for GPS, it may show you precision of 1m on the satellite view and still the position will be coupble of meters off the real one (not accurate).
Also the attached picture may be helpful to understand the difference.

To see how accrate the GPS is, it is better to see how the saved track match real position.
I didn't compare H1 with 66 or 67, but in comparison with my old Oregon H1 is much more accurate - Oregon has more tendency to "crawling" when left in the same place, and it can be off by 1-3 meters in places where H1 is exactly on the track I am walking/driving.
RFtinkerer
Posts: 6
Joined: Mon Jul 06, 2026 2:01 pm

Re: What GNSS accuracy values are you seeing?

Post by RFtinkerer »

I just went for a small hike with my H1i, firmware 10.13. Set manual to multiband GNSS; tracked multiple Galileo E1/E5, Beidou B1/B2, GPS L1/L5 bands, 5-12 depending. Reported accuracy was down to 7 ft. My 67i regularly reported 6 ft but I don't know if there is a difference in reality. I compared to my Fenix 7X during the hike. There wasn't much noticeable difference in recording...they both looked good and between a couple buildings diverged mostly equally by about 10 ft. swinging a bit either side of true.
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GPSrChive
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Joined: Fri Jan 20, 2017 11:29 pm

Re: What GNSS accuracy values are you seeing?

Post by GPSrChive »

6 ft, 7ft, zero difference in reality because this is just an 'estimate' anyway. No GPSr actually knows how accurate their reported position actually is. This number is just a 'best case scenario' based on ambient conditions.

But, it is fun to compare different devices and different chipsets etc to see what they report!

I am still amazed and in awe at what can be accomplished with a handheld device powered by a couple of AA batteries, and a handful of atomic clocks smaller than a Volkswagen Beetle orbiting >12k miles above the earth at 9k MPH.
Visit GPSrChive.com - a premier independent GPS information resource!
WallyGator
Posts: 137
Joined: Thu Mar 20, 2025 4:01 am
Location: USA

Re: What GNSS accuracy values are you seeing?

Post by WallyGator »

I was truly amazed back in ~2000 when I first purchased a Magellan GPS 315. I vividly remember getting it at Fry's Electronics, (Anaheim store) here in SoCal. No map. Accuracy was ~45 feet but I think that's when SA was disabled in 2000. Still, it was remarkable that it could locate me anywhere on the earth. I've been using these devices since then.

BTW, I've seen no better than 6 ft accuracy with the Touch 2 with multi-band enabled. Average is about 12 ft. with only GPS.
RFtinkerer
Posts: 6
Joined: Mon Jul 06, 2026 2:01 pm

Re: What GNSS accuracy values are you seeing?

Post by RFtinkerer »

I went on a 7.7 mile trail run and recorded the tracks on both my Fenix 7X and H1i plus using full multiband, 1s data recording tracks. I carried the H1i plus in my left hand (annoying but I suffer for SCIENCE) and wore my Fenix 7X on my left wrist to give them similar positions. Then I exported the tracks to Google Earth. The trail has some heavy tree covering but no canyons or anything weird so I expected good tracks and was not disappointed by either. The points were within a few feet of each other and where I could see the trail on the satellite picture, overlaying or within a few feet of the real trail. Even with my picky self I was more than happy with them both.
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