juniorLINQ

Difference between Count and LongCount

Updated May 16, 2026

Short answer

Count returns int; LongCount returns long.

Deep explanation

LongCount is used for very large sequences exceeding int.MaxValue.

Real-world example

Counting massive log entries.

Common mistakes

  • Using Count for huge datasets causing overflow.

Follow-up questions

  • Is Count expensive?
  • Does EF translate LongCount?

More LINQ interview questions

View all →