An NFC tag is the combination of an NFC chip, an NFC antenna and something that holds it all together. Choosing which NFC tag you need for your project can make all the difference to it's success.
There's no industry standard way of actually naming the different NFC items. However, to try and keep things simple, Seritag call items like hang tags, keyfobs, wristbands, PVC cards and so on 'NFC Products'. We (typically) use the term 'NFC Tags' only for NFC stickers and disc tags. For the sake of clarity, the term 'NFC label' will be considered the same as an NFC sticker. For those wanting to understand the difference between the different sticker types, then have a read through NFC tag formats. To help you visualise, here's a picture of an NFC tag (in this instance a clear sticker) :
And this is a disc tag :
There are a large number of different NFC chips available but in reality, when it comes to general availability and cost - there's really only three or four. To help you out, we've got a comparison of your NFC chip options.
Let's keep this simple. Use the biggest NFC tag you can, this is about the size of a credit card size (50mm x 80mm).
Sure, smaller tags look neater and arguably they are easier to handle but nothing is worse than having to hunt around to get a scan. A good size tag will scan easily and work well. The largest you want to go with a mobile phone is around 50mm. Anything bigger will often not work any better and can actually scan worse. 29/30mm is a good all round size and if you are pushed, then go down to a 22/25mm. Anything smaller is for specialist use or where you are really stuck for space.
If your tag is going indoors then most tags will work for you. If the tag is going outside, then you will need to use something that can handle the weather. Much of this will depend just how exposed your location or how extreme the temperatures.
At the 'not very exposed' end, if your tag is being stuck on a clean dry surface, you might just get away with a standard plastic face label. The plastic face will protect the tag and if the surface is clean, flat and dry, it'll usually hold in place like any other label.
In the middle, you can usually use a normal tag but can then apply a second tougher vinyl layer over the top. This will further seal in the NFC tag and provide protection from the sun and rain. You can purchase these more durable NFC stickers made up for you, but it's really just a one part version of doing the two parts yourself.
The top level will typically be a disc tag. These are fully sealed and IP rated (waterproof rated) plastic tags which can either be stuck or screwed into place.
Note that Seritag sell a PVC NFC disc tag which is more durable and 'knock resistant' than a standard label. However, we don't recommend using PVC disc tags outside as the PVC doesn't hold up well to the weather and has minimal UV resistance.
If your tag is going to hidden, for example inside a product or on the inside of packaging, then you probably want to go for the cheapest possible option. And that usually means a clear sticker. Clear stickers are technically the same as white ones so you get the same performance. It's purely aesthetics and if you aren't going to see it, why not save some money.
Additionally, clear tags (and inlays) are usually slightly thinner than white tags. If you are planning on laminating your tag between, say, two pieces of cardboard, then go for a clear tag. It'll be less visible.
Generally, disc tags are a lot more difficult to print on. If you want a logo then it can get quite expensive. If you want an ID, then it usually needs to be laser etched or inkjet printed. To then match that with encoding can be quite costly if it's not done during manufacture
If you need an ID print on your NFC stickers then that's usually quick and cheap and can be done either during manufacture or afterwards. Seritag can ID print and/or QR code print on almost all our white tags with a 24 hour lead time and encode to match.
If it's in a safe position and not likely to get knocked, then you can go for a normal sticker. However, if you think it might get knocked or hit in any way, then go for a disc tag. Generally, well made NFC tags are quite strong and they can take quite a lot of little knocks or even bends.
However, a direct hit on the chip (or more specifically the bond between the chip and the antenna) and you can destroy the tag. Disc tags are much more durable and some of the tougher nylon ones can take a direct hit with a hammer.
Let's break this down into two areas. What are you attaching it to and how are you intending to attach it.
First, can you attach your tag with adhesive or will it need to be screwed. If you can use adhesive then will normal adhesive or do you need thicker padded adhesive for uneven surfaces.
Most normal stickers can be attached to any clean, dry, flat surface and will adhere very well. However, Seritag can also provide tags such as PVC discs with a thicker padded adhesive which will attach better to rough surfaces.
If you are intending to screw the tag into place then you will need a plastic disc tag. Many options are available with a hole in the middle for easy fixing. Don't be tempted to just put a hole in a tag or disc tag that doesn't already have one. You can easily go through the chip or part of the antenna and end up breaking some or all the tags.
Secondly, are you attaching to metal. Normal NFC tags will not work on metal and you need to use a special on-metal NFC variant.
Fortunately, both NFC stickers and disc tags come in 'on-metal' variants so it rarely stops projects. However, on-metal tags often costs quite a bit more and can have a few more restrictions in terms of print. If you can avoid putting tags on metal, you will have a lot more options.
If you do require on-metal then consider where your tags will be placed. The additional barrier layer with on-metal tags can often be exposed and it doesn't handle weather and water very well. If your tags are going outside, make sure you choose a disc tag with enclosed barrier material.