LibKey Link (Original 1.0 Version for PubMed Only)


This LibKey Link page is now deprecated and is replaced by the *new* LibKey Link page found here.  This page is being kept up temporarily for reference for users transitioning between the original LibKey Link which only can be utilized by PubMed and the newer service that replaces it.

Detailed Overview of Functionality

The LibKey Link service dramatically simplifies how users get to a PDF when using PubMed.  Instead of the cumbersome, time consuming and often confusing process of clicking through buttons and links, LibKey Link provides true, one-click access from PubMed record to PDF.  If you are using either Link Out or the Outside Tool (otool) with PubMed, you may use LibKey Link.

What is the exact workflow that a user can expect?
Because the LibKey Link replaces your link resolver link in PubMed, the LibKey API is consulted first for every article request.  In a fraction of a second the LibKey technology will route the user in one of two directions:
  1. LibKey determines that it can route the user directly to the PDF document on the publisher's site based on the library's holdings and authentication data.  If it can do this, the user will see a very brief "LibKey" splash screen followed by either an authentication challenge for your proxy/OpenAthens system or they will immediately see the PDF!  If you have no remote authentication or are a VPN library, LibKey will also check the IP of the user to ensure they will have success before trying to link them off to the PDF.  If the user is deemed to be out of the IP range, LibKey will present a helpful message encouraging them to turn on their VPN or use the service from on-site, as appropriate.
  2. If LibKey determines that it CANNOT route the user to the PDF for any reason, part of the setup process with LibKey is that it is also aware of your link resolver base URL and so automatically routes the user to the link resolver using the exact linking you would be using without LibKey to ensure the user can get to the article even if they are doing so via the link resolver link.  When this route is chosen by LibKey there is no interface from LibKey displayed at all - the link resolver link is simply quickly loaded without delay.
In this way, LibKey greatly accelerates the access to content, minimizes clicks and removes confusion for a lot of content while ensuring that there is no loss in access for all your content.

Getting Started

How do I take advantage of LibKey Link?
First, you need to ensure your subscription with Third Iron includes LibKey Link!  If you are a Third Iron Complete customer (which includes all customers with a subscription who started their subscription before December 31, 2018) then you are eligible to use LibKey Link at no charge!  If you started after January 1, 2019 you will need to have an active subscription to either the LibKey Suite or Third Iron Complete.  Any questions about what your subscription includes, just email us at

Second, complete the LibKey Link sign up form.

You will then receive an email with the new URL to use in the Edit Outside Tool Information section the LinkOut Library Submission Utility, like this:

Once you add the new link, NLM advises that changes made to your URL will take place at 2 PM the next business day.  No additional steps or on going maintenance needed.

If you ever want to switch back to just using your standard link resolver, simply replace the LibKey Link with your standard link resolver base URL.  Easy!

Frequently Asked Questions

I heard PubMed will be making changes to LinkOut.  Will this still work? 
Yes!  NLM announced in March 2019 that they will be retiring the manual submission tool and LinkOut Local and merging the OTool utility into a service rebranded as Library LinkOut (which is essentially what OTool is today).  You can read the full announcement here. 

Will this work on mobile devices?
Not yet... but soon! NLM will be releasing a new mobile responsive version of PubMed which will incorporate Library LinkOut. Once released, LibKey Link will be especially useful for mobile users since it delivers true one-click access to PDFs. No tapping buttons and clicking links on small screens!

Will using LibKey Link mean I need to use a different otool icon/button?
No.  The LibKey Link is only a URL and does not affect the icon/button that you have setup in PubMed.

What publishers/platforms are supported by the LibKey Link service?
LibKey Link provides one-click access to millions of open access and subscribed PDFs from hundreds of publishers.  We are expanding these numbers every day and a current list of supported publishers and platforms is available here.

Can LibKey Link be used in other services where I use my link resolver link besides PubMed?
No.  LibKey Link is specifically designed for PubMed use only.

Additional Questions?
We are here to help! Drop us a line at!

Interested in learning more?  Our recent recorded webinar is available here:

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