Which NFC Tag ?

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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.

What exactly is and isn’t an NFC tag ?

There’s no industry standard way of actually naming the different NFC items. However, to try and keep things simple, let’s call items like hang tags, keyfobs, wristbands, PVC cards and so on ‘NFC Products’. We will then reserve the term ‘NFC Tags’ only for NFC stickers and for the purposes of this page disc tags. We don’t usually include disc tags as NFC Tags but we’ll make an exception here. 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) :

A clear NFC tag. Image : Seritag

And this is a disc tag :

A typical NFC disc tag. Image : Seritag

The 7 things to consider when buying NFC tags

1. Which NFC chip do you need ?

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.

2. How much space have you got ?

Let’s keep this simple. Use the biggest tag you can. 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 38/40mm. Anything bigger will often not work as well. 29/30mm is a good all round size and if you are pushed, then go to a 22/25mm. Anything smaller is for specialist use or where you are really stuck for space. If you can stick on a 38mm, then do so.

3. Is the tag going indoors or outdoors ?
If your tag is going indoors then you can use anything you like. 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 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. Word of warning. Don’t be tempted to use PVC cards or PVC ‘disc tags’ in these locations. Many of these haven’t had UV protection in the plastics and will quickly degrade and stock working.

4. Will your tag be hidden or visible ?

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.

5. Do you need printing such as a logo or ID number ?

Generally, disc tags are a lot more difficult to print on. If you want a logo then often it’ll cost a lot. 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 you need an ID print on your tags, then you need to choose a white tag.

6. Will your tag be in a safe or exposed position ?

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.

7. What exactly are you going to attach it to ?

This will typically come down to two aspect. Can you stick your tag on or will it need to be screwed. Secondly, are you attaching to metal. Normal NFC tags will not work on metal and you need to use a special on-metal 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.