Generally speaking, RFID tag maximum read distances are as follows:
125 kHz and 134.2 kHz
Usually 10 cm (4 inches)
It is possible to get read distances over 30cm (1 foot), but these cases need individual assessment.
Usually under 1 meter (3 feet)
To obtain more than 1 meter (5 feet) you need a reader with output over 1 watt.
Usually over 700 meters (2100 feet)
We've obtained reads over 2 kilometer (1.24 miles) away using FCC approved antennas.
Usually 50 meters (160 feet)
An emerging standard.
Currently up to 100 meter (325 foot) maximum
NOTE: 2.45GHz RFID is not the same as WiFi enabled Internet-of-Things devices which also work on the 2.4GHz band.
RFID is a group of technologies, usually identified by the frequency or "wave" they use. The maximum distance you'll achieve is influenced by;
...and several other factors. This complexity is why vendors usually use the "free air" read distance, or how well the tag performs in a perfect environment free of any other electrionics and onstacles. This gives you a good idea of what the best case situation is, but real life is usually quite a bit short of this mark since we enjoy access to WiFi and cellular signals, electric lights and computers.
SkyRFID test our equipment at the factory and at our North American offices using the most common arrangements we see for each invidual use case. The details we include on our spec sheets is what you'll get in normal use.
Read distance of 30 cm (1 foot) or less - usually 10 cm (4 inches) unless you are using a very large tag which can have a read distance of up to 2 meters when attached to metal. SkyRFID can provide several different LF 134.2 tags which produce read distances of 1 - 2 meters in industrial environments. We also have special readers that allow for a 1 - 2 meter read distance using standard size tags. There are no limits with SkyRFID!
Maximum read distance of 1.5 meters (4 foot 11 inches) - usually under 1 meter (3 feet) and you can use a single or multi port reader plus custom antennas to extend the read range to longer tag read distances or a wider RFID read zone. To obtain more than 1 meter you need a reader with more than 1 watt RFID output power. SkyRFID can supply 13.56 readers with RF power outputs up to 10 watts for multiple antenna connections and over 1 meter tag read distances.
Minimum read distance of over 1 meter or 3 feet. Gen2 tags can have a read range of over 16 meters or 52 feet when using the full 4 Watt EIRP legally allowed on the readers by FCC and other global regulators (For your local power regulations see our RFID Education page). Gen 2 tags can be EPCglobal multi-frequency, 860 MHz. European Union, or 902 MHz. FCC depending on the tags function and other capabilities. Gen 2 semi-passive (semi-active) tags are battery assisted and have a read range of up to 50 meters or about 162 feet. We have both passive and the emerging semi-active readers and tags available for those companies that need to be on the leading edge or simply need the range of the Gen 2 Semi-active technology.
Usually LF and SHF. Now you can have a UHF RTLS that is extremely accurate and can easily control 250,000 sq feet on a single switch. Use the Contact Usfor more information.
Adjustable read range from 30cm (1 foot) to over 2 kilometer (1.24 miles) using highly sensitive FCC approved antennas. SkyRFID carries a complete line of 433 MHz readers and tags that can be used for many industrial,healthcare, mining, and other tracking and locating applications.
Up to 100 meter read range (325 feet) There are several different modulations for 2.45 GHz. and you can also have real time location information from these active tags.