- Cleasby-Vigfússon Online — There are now a couple of digitized versions of the standard (Old) Icelandic-English dictionary on the web. You can get it from Northvegr, but the one produced at the University of Pennsylvania is perhaps easier to use, since it has both scanned page-images and an html version. You can of course still buy Cleasby-Vigfússon, but the existence of freely-available copies has hardly prompted OUP to lower the price!
- Fritzner’s Ordbog Online — The standard dictionary of Old Norse (for anybody who reads Norwegian, at any rate) now available in a searchable electronic form at the University of Oslo.
- Online Modern Icelandic Dictionary — Sverrir Hólmarsson, Christopher Sanders and John Tucker, Íslensk-ensk orðabók / Concise Icelandic-English Dictionary (Reykjavík: Iðunn, 1989). Fully searchable and containing a grammar and a selection of readings for learners.
- Ordbog over det norrøne prosasprog / A Dictionary of Old Norse Prose — The homepage of the Copenhagen Dictionary project. Will it ever be finished? The online key and register are particularly useful, but the whole dictionary is only available in hard-copy.
- Zoëga: Concise Icelandic Dictionary online — Scanned text of Geir T. Zoëga’s 1910 dictionary of Old Norse (now back in print from University of Toronto press: available from amazon).
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