Virtual reality on your smartphone

We want everyone to experience virtual reality in a simple, fun, and inexpensive way. That's the goal of the Cardboard project.

Watch our I/O 2014 Tech Talk about Virtual Reality for Android

Virtual reality has made exciting progress over the past several years. However, developing for VR still requires expensive, specialized hardware. Thinking about how to make VR accessible to more people, a group of VR enthusiasts at Google experimented with using a smartphone to drive VR experiences.

The result is Cardboard, a no-frills enclosure that transforms a phone into a basic VR headset, and the accompanying open software toolkit that makes writing VR software as simple as building a web or mobile app.

By making it easy and inexpensive to experiment with VR, we hope to encourage developers to build the next generation of immersive digital experiences and make them available to everyone.


Build your own

Construct a VR viewer from everyday items you can find in your garage, online or at your local hardware store.

Here's what you need to get started:

Cardboard ingredients
  1. Cardboard
    Corrugated cardboard sheet, preferably E Flute (corrugated cardboard comes in a variety of thicknesses called "flutes"), available at many art supply stores and online . For best results, you should look for strong, thin cardboard (sturdy shoe box rather than moving box). Minimum size: 8.75in (22cm) by 22in (56cm), and 0.06in (1.5mm) thickness. Online sources here and here
  2. Lenses
    This is the trickiest component. Lenses that have a 45mm focal distance might work. Biconvex lenses work best because they prevent distortion around the edges. We used the Durovis OpenDive Lens Kit available here (US) and here (EU).
  3. Magnets
    One neodymium ring magnet - like this or this - and one ceramic disk magnet - like this or this. Approximate size: 0.75in (19mm) diameter and 0.12in (3mm) thickness.
  4. Velcro
    Two strips of regular strength adhesive-backed velcro. Approximate size: 0.75in (20mm) by 1.25in (30mm).
  5. Rubber band
    One rubber band, to prevent the phone from sliding out. Minimum length of 3.2in (8cm).
  6. NFC tag (optional)
    One sticker NFC tag. Program it with the URL cardboard://v1.0.0

You'll also need a ruler, glue, and scissors, an X-acto knife, or access to a laser cutter.


Code your own

Use the experimental VR Toolkit to build immersive experiences that work with Cardboard and other viewers.

We've created a tutorial and provided documentation to get you started. Because this SDK is experimental, it won't receive the same level of support as core Android SDKs and libraries.

Things may change or break as we continue working, but the projects you build and feedback you provide will guide subsequent versions.


Your questions answered

How did the Cardboard project start?

David Coz and Damien Henry at the Google Cultural Institute in Paris built a cardboard smartphone housing to prototype VR experiences as part of a 20% project. The results elicited so many oohs and ahs that they inspired a larger group to work on an experimental SDK.

Will Cardboard work with my phone?

Cardboard works with most modern Android phones. Phones need to be running Android 4.1 (Jelly Bean) or above. Ideally they should support NFC too.

Here is a list of the phones we've tested that are compatible with Cardboard.

  • Fully compatible
    • Google Nexus 4 and 5
    • Motorola Moto X
    • Samsung Galaxy S4 and S5
    • Samsung Galaxy Nexus
  • Partially compatible
    • Magnetic input not working
      • HTC One
      • Motorola Moto G
    • Magnetic input not working & headtracking/rendering issues
      • Samsung Galaxy S3

Can I use cardboard even if I wear glasses?

Yes. You may want to cut flaps into both sides of the viewer. There's a fold line pre-cut into both sides of the viewer to make this easier.

What if my phone doesn't do anything when I insert it into Cardboard?

Make sure that you have NFC turned on. Also make sure that you have the Cardboard Android app installed.

How can I test my own application without having the cardboard demo popup when I insert the phone?

The best method is to set your app to handle the NFC URL: cardboard://v.1.0.0. Alternatively, you can disable NFC in your phone's settings.

When I try to view the Chrome VR site using Cardboard, the demo launches. How do I prevent this?

Install the Cardboard Android app and let it always handle the NFC event from the Cardboard viewer. The Cardboard app will not launch when you have another app in the foreground.

You can also disable NFC in your phone's settings.

What are the magnets for and can I use cardboard without them?

The magnet is used for clicking inside of demos. When you pull and release the ring, your phone's magnetometer detects changes in the magnetic field. Chrome experiments currently don't use the magnet, but you will need it to try the Cardboard Android app.

Not all phones will be able to detect magnet pulls. You can use Cardboard without the magnet by sticking copper tape along the side of the viewer and having it come into contact with the phone screen. When you tap twice on the copper tape with your finger, the phone will react as if it had detected a magnet pull.

What does the NFC tag do and can I use the Cardboard app without NFC?

NFC is used to trigger the launch of the Cardboard Android app automatically. You can also start the Cardboard app from the Android launcher before putting your phone inside the viewer.

What does it mean that the VR Toolkit is experimental?

It means we won't support the VR Toolkit at the same level or quality that we support core Android SDKs and libraries. And things may change or break as we continue working on it.

We are sharing it at this early stage to give developers the chance to experiment with it as we do.

Where can I get help or give feedback about Cardboard?

Please join our G+ community.

Where are the spherical videos in the VR Chrome Experiment from?

The spherical videos are provided courtesy of AirPano.

Can I use a pizza box for the cardboard?

Yes. Make sure you order an extra large.