magicWhat is an Irish surname generator?
An Irish surname generator picks random Irish family names for characters, games, role-play or exploring heritage. Each name here comes with its traditional meaning, many of them describing an ancestor: a warrior, a chief, a red-haired or dark-eyed man.
Most Irish surnames began as Gaelic names meaning “descendant of” or “son of” someone, which is where the O' and Mac (or Mc) prefixes come from.
How to use it
- Generate surnamesThe tool opens on Irish surnames. Press Generate for 5, or choose up to 50.
- Read the meaningsMeanings are on: Ryan is “little king”, Phelan is “wolf”, Doyle is “dark stranger”.
- Add a first nameType a first name like Siobhan or Ciaran to see full names, then copy.
What O', Mac and Fitz mean
| Prefix | Meaning | Examples |
|---|---|---|
| O' (Ó) | grandson, descendant of | O'Brien, O'Neill, O'Sullivan |
| Mac / Mc | son of | McCarthy, McGrath, McLoughlin |
| Fitz | son of (Norman French) | Fitzgerald, Fitzpatrick |
| no prefix | prefix dropped over time | Murphy (Ó Murchadha), Kelly (Ó Ceallaigh) |
Why some Irish names lost their O'
Under English rule, many families anglicised their names and dropped the O' or Mac, so Ó Murchadha became Murphy and Ó Ceallaigh became Kelly. From the late 1800s and into the 1900s, during the Gaelic revival, many families took the prefix back, which is why you'll find both Sullivan and O'Sullivan today.
Norman settlers brought Fitz- names (from the French fils, son) and names like Burke, which became thoroughly Irish over the centuries.
Frequently asked questions
What is the most common Irish surname?
Murphy is the most common surname in Ireland, followed by Kelly, O'Sullivan, Walsh and O'Brien. All are in the generator.
What's the difference between O' and Mac?
O' (from Ó) means grandson or descendant of, and Mac means son of. Both point back to a named ancestor: O'Brien is a descendant of Brian.
Is Mc different from Mac?
No. Mc is a shortened spelling of Mac; both mean “son of” and are used in Irish and Scottish names.
Can I use these for characters?
Yes. They're real surnames, so they give Irish characters an authentic feel.
Are the meanings certain?
They're the traditional meanings. Old Gaelic names can be read in more than one way, so treat them as the most common interpretation.
Last updated 2026-11-03. This tool runs in your browser; nothing you type is sent to our servers.