“may” vs. “might”
Use "may" for a live, reasonably likely possibility or formal permission, and "might" for a more remote, more tentative possibility, or as the past tense of "may" in reported speech.
may
"May" expresses a real possibility that's still fairly likely, or grants permission ("you may leave early," "it may rain today"). "May" descends from Old English "mæg," originally meaning "to be able" or "to have power," the same root that gives us "main" (as in physical strength, preserved in the phrase "with might and main") and, further back, connects to the same Germanic root behind "might" itself.
might
"Might" expresses a weaker, more remote or hypothetical possibility ("it might rain, but I doubt it"), and also functions as the past-tense form of "may" in reported speech ("she said it may rain" becomes "she said it might rain"). "Might" comes from Old English "meahte/mihte," originally the past-tense form of "magan" (the ancestor of "may"), which is exactly why "might" still functions as "may"'s past tense today even though in everyday use it's drifted into its own separate, present-tense role expressing weaker possibility.
The real distinction
Because "might" was historically just the past tense of "may," the two verbs are etymological relatives, not an arbitrary pair — but modern English has repurposed that old past-tense form to do double duty as a marker of lower probability in the present tense as well. The practical distinction most style guides teach: "may" suggests something is reasonably likely or is a live possibility ("I may go to the party" — a real, live plan), while "might" suggests something more remote, more tentative, or explicitly less likely ("I might go to the party, but I'm exhausted" — less committed, less likely). This distinction is genuinely a matter of degree rather than a hard binary, and even careful writers disagree at the margins about exactly how much less likely "might" implies compared to "may." A separate, entirely unrelated use of "may" is granting or requesting permission ("may I leave early?"), a formal register that "might" can also fill in especially polite or tentative requests ("might I ask a question?"), where "might" softens the request even further than "may" already does. In reported or indirect speech, sequence-of-tense rules require converting a present-tense "may" in the original quotation into "might" in the reported version, a rule some writers get backward, incorrectly leaving "may" in place after a past-tense reporting verb ("she said it may rain" instead of the more standard "she said it might rain"). A further wrinkle appears in conditional sentences describing an unrealized past event: "if I had known, I might have called" uses "might have" to express something that was possible but didn't happen, while swapping in "may have" ("if I had known, I may have called") sounds noticeably less idiomatic to most native speakers even though both are grammatically defensible, since "might have" more clearly signals a hypothetical that never occurred. Editors reviewing scientific and news writing specifically watch for overconfident use of "may" where the underlying evidence really only supports the weaker "might," since overstating certainty by picking the wrong modal verb can quietly misrepresent how solid a claim actually is.
Examples with “may”
- We may leave early if the traffic gets bad.
- You may borrow my umbrella today.
- She may already know about the surprise.
- The meeting may run longer than planned.
- He may be the best candidate for the role.
- May I ask you a quick question?
- They may release the results tomorrow.
- It may take a few days to arrive.
Examples with “might”
- It might rain later, but the forecast isn't sure.
- I might take the job if the salary improves.
- She might have missed the announcement entirely.
- We might visit next year, depending on our budget.
- He might change his mind after hearing the details.
- Might I suggest a different approach?
- They might have already left by the time we called.
- The results might not be ready until next week.
Memory trick
Both "might" and "maybe not" carry a lower-confidence feel, while "may" pairs naturally with a more confident, live possibility — think of "might" as "may, but less sure." One more useful check for reported speech: if the original quotation used "may" and you're now reporting it after a past-tense verb like "said" or "thought," shift it to "might" to keep the tenses consistent.