RFID Scan distances

Hey I’m trying to find a RFID scanner, proximity or vicinity that will allow for the RFID chip to be scanned further away from the scanner rather than right on top of, 100mm range should do it.

For an escape room, gamer finds a foot in an esky and must put it on an area but trying to make it that we don’t have to stencil the foot and orientation because it’ll be to obvious so a range off a 100mm rather than directly on top will fix this I hope.

Thanks for your help Jimmy


Hi Jimmy, welcome to the forum!

Seems like Adafruit’s best have already worked this one out in their NFC shield:

The Adafruit shield was designed by RF engineers using the best test equipment to create a layout and antenna with 10cm (4 inch) range, the maximum range possible using the 13.56MHz technology. You can easily attach the shield behind a plastic plate with standoffs and still read cards through a (non-metal) barrier.

So it seems 100mm would be pushing it, but may work.

Keen to hear what this means for you! Maybe a camera on the ceiling that can recognise the foot may be the go? It might be hard to distinguish from a hand in the same place however…



Hi Jimmy, James
I think some research has to happen to ascertain the best frequency that suits your use. Also to be factored in would be availability and cost.
There is some pretty good info here Understanding choosing RFID tag based on the tag frequency
Antenna size and type would have to be considered.
One limiting factor would be that the electronics in a passive tag have to be powered entirely by the incoming energy transmitted from the reader then be sensitive enough to respond to a reply which you can imagine would be transmitted in Pico or Nano Watts. This would also have an influence on distance.

The tags used on Road Toll systems seem to work pretty well but because of the nature of the site the best available antenna system could be easily used.

When I first read this Post I thought you said 100 metres and I thought good luck with that but then on re reading (always pays to check) the proposal turned out to be not so outlandish.
Cheers Bob