It seems that there are different versions of the Arduino Ethernet Shield available. How can I distinguish between the versions? How do I find out which hardware version I have?

Update: Arduino Ethernet Shield Front- and Backside Since Kevin Mark added an answer I post an image of my Ethernet Shield:

  • \$\begingroup\$ Do you know where you got it from? That could help, as some stores only sell one revision of a product, not all of them. \$\endgroup\$
    – Polar
    Apr 17, 2013 at 15:51
  • 3
    \$\begingroup\$ @Kaz: Actually it's ignorant to not use the correct naming. The Arduino daughter boards are really named "shields". I do also think that the name is chosen very badly, but that's the way it is. \$\endgroup\$
    – Tom L.
    Apr 26, 2013 at 7:22
  • \$\begingroup\$ @Kaz A shield is a valid name, and the official one decided upon by the brand owner, by the for a daughterboard as applied to devices designed for the Arduino platform, just as a "PCI card" is a perfectly valid term for a daughterboard of a specific format. It's here to stay, one can either live with it, or just ignore the question - no value to trying to push that "it's a daughterboard" point. \$\endgroup\$ Apr 26, 2013 at 17:29
  • \$\begingroup\$ So if they put "Capacitor" on the silk screen, I'd be ignorant not to call it an Ethernet Capacitor? You two would eat your words in that situation, I'm afraid. There is value in pushing the "it's a daughterboard" point, because it helps the Arduino crowd not to look like buffoons. Those Arduino users who do not actually know that the rest of the world doesn't call it "shield" deserve to know that. \$\endgroup\$
    – Kaz
    Apr 26, 2013 at 17:52

2 Answers 2


There should be an R3 (or similar) revision number on the bottom. If your board contains a full-size SD card slot then it is the original.

enter image description here

  • \$\begingroup\$ Which version numbers are already given? \$\endgroup\$
    – powtac
    Apr 17, 2013 at 12:06
  • \$\begingroup\$ my shield has no number! See updated question. \$\endgroup\$
    – powtac
    Apr 17, 2013 at 12:24
  • \$\begingroup\$ @powtac If your board contains a full-size SD card slot then it is the original. \$\endgroup\$
    – Kevin Mark
    Apr 23, 2013 at 0:25
  • \$\begingroup\$ IIRC the build without a version number was the original release. \$\endgroup\$ Apr 26, 2013 at 14:47

There wasn't an R2. There's only the original and R3. It was given the R3 designation to follow the same conventions for the Uno and Mega2560 R3. The "R3" of the ethernet shield only added pin headers, which matched the "new" headers of the R3-Uno and R3-Mega. The pins added were:

1) Dedicated SCL and SDA next to AREF.
2) IOREF next to RESET and N/C next to IOREF

No actual hardware changes were implemented.

  • \$\begingroup\$ @AnnonomusPerson No. Header spacing is consistant across all official Arduino boards and shields. \$\endgroup\$ Apr 20, 2013 at 18:25
  • \$\begingroup\$ I thought on some newer boards they were standard spaced. I also read that only the newest shield is Mega compatible, and you said no hardware changes were implemented. Sorry. \$\endgroup\$ Apr 20, 2013 at 18:32

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.