OpenTag NFC standard in SimplyPrint
Written By Albert Møller Nielsen
Last updated About 4 hours ago
OpenTag NFC standard in SimplyPrint
Looking for a future-proof, open-source NFC standard backed by multiple filament manufacturers? OpenTag3D is a community-driven specification designed to work across all 3D printer brands, filament makers, and accessory providers. SimplyPrint fully supports reading and writing OpenTag tags - giving you a standardized way to tag your spools that should work with many devices and ecosystems as adoption grows.
This article covers everything about using OpenTag with SimplyPrint. For a general introduction to NFC in 3D printing, hardware options, and step-by-step guides, see our main NFC article.
NFC support in SimplyPrint
SimplyPrint has deep NFC integration across our entire platform - both the web panel and mobile apps for iOS and Android. We support reading and writing NFC tags in multiple formats, allowing you to work with filament from various brands and make your spools work with different printer ecosystems.
What you can do with NFC in SimplyPrint:
- Read NFC tags to instantly identify spools and see their details
- Write NFC tags in various formats - OpenTag, OpenPrintTag, OpenSpool, Creality, QIDI, Anycubic, and more
- Link physical spools to their "digital twin" in your filament inventory
- Quickly assign spools to printers by scanning instead of scrolling through lists
How you can read and write NFC:
- Mobile apps (iOS & Android) - most phones have built-in NFC, making this the easiest method
- Desktop USB readers - for those who prefer working from their computer
For the full breakdown of hardware options, supported methods, and step-by-step guides, check out our main NFC article.
What is OpenTag3D?
OpenTag3D is an open-source NFC standard designed specifically for the 3D printing industry. Unlike vendor-specific formats, OpenTag was built from the ground up to be a universal standard that any printer manufacturer, filament brand, or accessory maker can adopt.
The origin story
OpenTag3D - originally called "Open 3D-RFID" - was initially drafted by Polar Filament and incubated within the Bambu Research Group. This group focused on reverse-engineering RFID tag data from Bambu Lab's filament spools to understand how NFC could benefit the broader community.
When Bambu Lab launched their own proprietary, encrypted format, the group recognized that other manufacturers would likely follow with their own incompatible standards. Rather than let the industry fragment, they moved the protocol to its own repository to create a truly open, vendor-neutral standard.
The consortium model
OpenTag3D is governed by the OpenTag3D Consortium - a collaborative group of 3D printing companies, hobbyists, RFID experts, and other stakeholders. The consortium operates under a structured membership model that balances industry representatives and community representatives equally.
Current voting members:
- Gooborg Studios
- Polar Filament
Supporting filament manufacturers:
- Polar Filament
- American Filament
- Numakers
- 3D Fuel
- Ecogenesis Biopolymers
Supporting hardware providers:
- OpenSpool
- Cosmyx
- Distrifab
Official resources
- Website: https://opentag3d.info/
- GitHub: https://github.com/queengooborg/OpenTag3D
- Specification: https://opentag3d.info/spec.html
- License: GPL-3.0 (open source)
OpenTag3D is still being finalized - the current specification version is 0.020. The standard is expected to be fully finalized in 2025, with growing industry adoption.
What can SimplyPrint do with OpenTag?
SimplyPrint fully supports the OpenTag3D standard. Here's what you can do:
- Write OpenTag NFC tags for any filament in your inventory - stick them on your spools
- Read existing OpenTag tags - if you receive a spool with an OpenTag tag, we can read it
- Link tags to your inventory - connect physical tags to their digital twin in your filament manager
- Quickly identify spools by scanning - no more guessing which spool is which
- Write remaining filament data - OpenTag supports storing current weight and length measurements
For hardware requirements and step-by-step instructions on reading/writing NFC tags, see our NFC hardware & methods guide.
Important: What SimplyPrint can and can't do
Let's be clear about what works and what doesn't:
What works great
Easy tag writing - Create OpenTag tags for any filament in your SimplyPrint inventory. The format stores comprehensive data including temperatures, density, and color.
Full iOS and Android support - OpenTag uses standard NTAG tags, which work on both platforms without limitations.
Web NFC support - You can write OpenTag tags directly from a browser on Android devices - no app needed.
Cheap, widely available tags - NTAG213, NTAG215, and NTAG216 tags are common and inexpensive.
Remaining filament tracking - Unlike some other standards, OpenTag can store your current remaining weight and length on the tag itself.
Fast spool identification - Scan any tagged spool with your phone or desktop reader to instantly see which spool it is in SimplyPrint.
What doesn't work
No automatic sync from the printer - This is a general limitation. If a future printer reads your OpenTag and uses it, SimplyPrint won't automatically know about it. There's no communication back to us.
Automatic material syncing - where the printer tells SimplyPrint what's loaded - is currently only available for Bambu Lab AMS (when using Bambu's own tags).
You'll need to manually assign spools in SimplyPrint - After loading filament, you'll still need to tell SimplyPrint which spool is on which printer. The good news? With NFC tags, this takes seconds: scan the tag, tap assign, done.
Still gaining adoption - As a newer standard that's still being finalized, printer support is still developing. Many filament brands are committed to the standard, but widespread printer integration is expected to grow throughout 2025 and beyond.
What data does an OpenTag tag store?
OpenTag has one of the most comprehensive data formats among open NFC standards. It uses a two-tier structure:
Core data (fits on all tags)
Extended data (larger tags only)
Do I need to worry about this format?
Nope! When you write an OpenTag via SimplyPrint, we pull all the relevant data from your spool in the filament manager and format it correctly. You don't need to think about any of these fields - just select OpenTag as the format and we handle the rest.
OpenTag's comprehensive data format means printers that support it will have all the information needed to automatically set temperatures, detect material types, and more.
What NFC tags does it use?
OpenTag supports standard NTAG tags, with different options depending on how much data you want to store:
For the best experience, we recommend NTAG215 or NTAG216 tags - they have enough space for all the data OpenTag can store, including extended fields like remaining filament tracking.
Where to buy compatible tags
Some links are affiliate links - we may earn a commission at no extra cost to you.
NTAG tags are the same ones used for many consumer applications like Amiibo cards. They're widely available, cheap, and work with virtually all phones and readers.
Compatible hardware for writing tags
OpenTag uses standard NTAG tags, making it very easy to work with:
This broad compatibility is one of OpenTag's strengths - you can use almost any NFC hardware to read and write tags.
For detailed hardware options, setup instructions, and where to buy readers, see our NFC hardware & methods guide.
Why use OpenTag via SimplyPrint?
1. Industry backing and future-proofing
OpenTag isn't a hobby project - it's backed by a consortium of filament manufacturers and hardware providers. As adoption grows, tags you write today should work with future printers and tools that support the standard.
2. Comprehensive data storage
OpenTag stores more information than most other open standards. Temperatures, density, color (including multi-color support in the spec), remaining filament - it's all there. This means better compatibility with smart features as printers evolve.
3. Remaining filament tracking
Unlike some standards, OpenTag has dedicated fields for storing how much filament is left on a spool. When you update your inventory in SimplyPrint, we can write that data to the tag too.
4. Works with any filament
OpenTag doesn't care where your filament came from. Budget brand, premium manufacturer, or mystery spool from the garage sale - write an OpenTag and it's ready for any compatible reader.
5. Cheap and universal tags
NTAG tags are among the cheapest and most widely available NFC tags. No special proprietary tags needed.
6. Cross-platform friendly
Full support on iOS, Android, Web NFC, and desktop readers. No platform lock-in.
7. Consistent workflow
Whether you're writing OpenTag, OpenSpool, Creality, or any other standard, the process in SimplyPrint is the same. Learn it once, use it everywhere.
Which printers and hardware support OpenTag?
OpenTag is still in the finalization phase, so native printer support is limited - for now. Here's the current landscape:
Committed supporters
Filament manufacturers - Polar Filament, American Filament, Numakers, 3D Fuel, and Ecogenesis Biopolymers have committed to the OpenTag standard. Expect to see spools with OpenTag tags from these brands.
Hardware providers - OpenSpool hardware is expected to support OpenTag-formatted tags once the standard is finalized.
Future adoption
The OpenTag3D Consortium is actively working with printer and hardware manufacturers to encourage adoption. The goal is for OpenTag to become a universal standard that works across the industry.
Even if your printer doesn't read OpenTag natively yet, you can still use SimplyPrint to write OpenTag tags for inventory management and quick identification via our app.
OpenTag vs other standards
How does OpenTag compare to other open standards?
OpenTag's strengths:
- Most comprehensive data format among NTAG-based standards
- Consortium governance (not tied to one company)
- Multiple filament brand commitments
- Remaining filament tracking support
Consideration:
- Still being finalized (but close to v1.0)
Limitations
Every standard has trade-offs:
OpenTag's data-rich format is designed for the future. While printer support is still growing, the tags you write today will be ready when adoption increases.
Getting started with OpenTag
Just want NFC tags for inventory?
- Create your filament spools in SimplyPrint's Filament Manager
- Use the app or web to write OpenTag tags for your spools
- Stick the tags on your spools
- Scan anytime to quickly identify and assign spools
Want remaining filament tracking?
- Write an OpenTag for your spool
- As you print and your inventory updates in SimplyPrint, re-write the tag
- The tag now stores the current remaining weight and length
Planning for future compatibility?
- Use NTAG215 or NTAG216 tags for full extended data support
- Write comprehensive OpenTag data via SimplyPrint
- Your tags will be ready for any future printers or hardware that adopt the standard
Quick reference
Related articles
- NFC / RFID support in SimplyPrint - Hardware, methods, and step-by-step guides
- The filament manager feature - Managing your filament inventory
- OpenSpool standard - Community open standard with DIY reader hardware
- OpenPrintTag standard - Prusa's open NFC standard