The Altmetric Advanced search allows you to search for multiple identifiers at once. There is a list here of all the identifiers Altmetric supports.
To start you will need to click on the Advance Search button.
Once in the Advanced Search you can click on Add Scholarly Identifiers. This should open a new window.
You can then add up to 25,000 of any type of identifier tracked by Altmetric. You can search by multiple types of identifiers (e.g DOI and arXiv) or just by one (e.g PMID). The text at the bottom of the box will tell you how many identifiers you have. N.B the search box does not recognise duplicates, so if you add 10 identifiers but 2 are duplicates it will still say 10 identifiers.
Once you've added your identifiers you can click Save. This should bring you back to the Advanced Search window, you will now see that the duplicates have been counted properly.
You can now click Search to see the relevant search results.
If you look on the right hand side you can see the Overview panel.
This panel shows how many outputs Altmetric knows about and how many of those outputs have mentions. While there were 20 DOIs, 1 URI, and 1 Handle in our search it looks like Altmetric only has 17 in the Explorer. Of those 17 outputs 8 of them have mentions tracked by Altmetric.
Research outputs: Items in the Explorer to which Altmetric has tracked attention or for which we've created a transparent citation. We have more information here about transparent donuts.
Outputs with mentions: Items in the Explorer to which Altmetric has tracked attention
To suggest a journal to be tracked you can email firstname.lastname@example.org.