English UsageComparison guide

Login vs. Log In

“Log in” is the phrasal verb for connecting to a computer system. “Login” is a noun for the credentials, act, or access point, and Cambridge also documents “log-in” as a noun spelling. The verb remains two words.

Quick answer

Use “log in” for the verb. Use “login” for the noun; Cambridge also records the hyphenated noun variant “log-in.”

Key details

Confusion Familyword-boundary
Noun Variant Scopeclosed login and hyphenated log-in are documented noun forms
Rule Familyorthographic-boundary
Termslogin, log-in, log in

Choose the right form

Decision table for Login vs. Log In
If you mean / needUseWhy
to connect to a computer systemlog inIt is the phrasal verb.
the credentials, act, or access point as a nounlogin / log-inBoth noun spellings are documented.

Further guidance

Core difference

The action is “log in”; the noun is commonly “login,” with “log-in” also documented.

Fast Test

If you can say “logged in” or “logging in,” you are using the two-word verb.

Variant Boundary

Cambridge records “login” and “log-in” as noun forms, so house style may choose between documented noun spellings.

Sources and evidence

Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.

  1. LOGIN — English meaning (opens in a new tab)Cambridge Dictionary · Noun meanings and documented “log-in” variant for “login”
  2. LOG IN — English meaning (opens in a new tab)Cambridge Dictionary · Phrasal verb “log in” for connecting to a computer system

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