G-Shock GDF-100 Review


IMG_2132_edited-1.jpgThe GDF-100 is one of Casio's newest models only being announced officially mid-March (see original news item here). Unlike many of the mid-high end G-Shocks the GDF-100 is readily available from both the high street and online retailers.

So, onto the watch itself, the model reviewed is the GDF-100-1AER. First impressions are good. [PRBREAK][/PRBREAK]The watch comes well packed as expected with a card outer and a metal 'nut box' (unlike the more normal plastic ones). The watch is large, approx 47mm diameter excluding buttons (for comparison a GW-9200 Riseman is 44mm) and well made as one has come to expect of Casio G-shock line up. The black resin is a little more matt than normal, the band is double slotted and the metal clasp has a slightly brushed finished. The display is clear and crisp, the digits being slightly larger than Casio's normal offering.

The 'headline' features of this watch are as follows

  • Altimeter
  • Barometer
  • Thermometer
  • EL
  • World Time
  • 24h stopwatch
  • 24h countdown timer
  • Alarm
The altimeter, barometer and thermometer functions of these Casio watches have been discussed ad-inifinitum elsewhere. As long as you understand the flaws of Casio's system they are perfectly useable. For comparison the watch read barometric pressure and temperature within 2% of my home weather station and GW-9200 Riseman. One big disappointment is the lack of barometric reading in the normal time mode - one of the best GW-9200 features is an indication of rise in fall of barometric pressure in normal time mode. This feature was even present on the far earlier DW-6500. The 'red eye' is a simple seconds counter normally, it is only use to show a rise or fall in pressure in the barometric pressure screen.

IMG_2211_edited-1.jpgThe EL is one of the watches most interesting features. Have tried to capture this in the image, however think my EL photographing skills need some work. Rather than the normal green EL which illuminates the entire screen there appears to be LEDs arranged around the GDF-100 screen which illuminate the screen in crisp white light.
The remaining features are fairly run of the mill. World time. Alarm and hourly chime. 24 hour stopwatch and 24 hour countdown timer - two features which are in demand by some. The current time is also visible on these screens.

On the wrist the watch wears like any other large G-Shock. The case sat well across the top of my 7 ½” wrist and the strap was well countered away from the watch giving the GDF-100 a snug and comfortable fit. It’s a big watch of course but feels fine on; it lacks the heft and height of something like a GW-200 Frogman. Visually it’s an imposing piece and is instantly recognisable as a G-Shock thanks to its looks and of course the red G EL button. This size may not be too everyone’s taste, it does almost seem to be big for the sake of being big. The LCD display is a slight departure from previous Casio offerings, will have to spend a little time with this to draw an opinion. The sensor protrusion on the left of the case may not be to everyone’s liking, further it may cause issue for those who wear their watches on their right. A size comparison of the GDF-100 with the GW-M5600 and GW-9200 can be seen in the thumbnails below.

IMG_2177.jpgThe watch is not solar nor does it have any waveceptor functions. Two features which are becoming almost expected on Casio’s mid to high end offerings. Only time will tell how long the battery will last with regular EL and twin sensor use.



  • Large and well made
  • Twin sensor
  • Larger than normal digits
  • Comfortable and fits well
  • 24 hour stw and cdt – both showing current time

  • Large – perhaps too large for some
  • No barometric display in the home screen
  • No solar or waveceptor
  • Lack of button at 2 o’clock seems unusual
To sum up another top G-Shock from Casio. It’s good to see the Japanese company trying something a little different. However at the watches price point I’d be sorely tempted to put the extra towards the GW-9200 Riseman which is an obvious competitor. Will I keep the review model? Let me think about it….

G-Shockzone Rating 6.5/10
The watch is available from ebay and amazon.co.uk .

Complete unboxing and review pictures can be seen below -



New Member
Nice watch I also considered the Riseman but (sadly) its pricey on ebay and amazon bur I can find this for around $75 on amazon or ebay


New Member
For the thermometer and barometer thermometer need to be calibrated bur the altimeter isn't as accurate as id like it to be but overall a good watch. now i wonder how much id like the riseman in comparison to my GDF100