Estimates for personal planning — not tax, legal, or payroll advice. Every number above is gross pay unless a line says otherwise; the formula, its boundaries, and its test cases are published below.
How it works
biweekly = $65,000 ÷ 26 = $2,500.00
semimonthly = $65,000 ÷ 24 = $2,708.33
// 26 checks ≠ 24 checks — same salary, different rhythm
Biweekly (26) vs semimonthly (24)
Biweekly means every other week — 52 ÷ 2 = 26 checks. Semimonthly means twice a month — 24 checks. On $65,000 that's $2,500.00 vs $2,708.33 per check: the biweekly check is smaller, but you get two more of them. Annual totals are identical.
The two 3-paycheck months
12 months × 2 checks accounts for only 24 of your 26 biweekly checks. The other two land as third checks in two calendar months — which months depends only on your first pay date of the year. Trace any pay date forward in 14-day steps and you'll find them.
Budgeting on a biweekly rhythm
The steady move: budget monthly expenses against just two checks ($5,000.00 on the default), and treat the two extra checks (2 × $2,500.00 = a 13th “month”) as savings, debt paydown, or slack — money your monthly budget never sees.
Biweekly, bimonthly, semimonthly — the words people mix up
Biweekly is every two weeks: 26 checks. Semimonthly is twice a month: 24 checks. Bimonthly ambiguously means either every two months or twice a month, which is precisely why payroll departments avoid the word. If a job posting says “bimonthly pay,” ask which one they mean — the difference between 24 and 26 checks changes every budget line you'll build around it.
Finding your two three-paycheck months
Take your first pay date of the year and add 14 days repeatedly. Two calendar months will contain three of those dates. Those checks aren't extra money — your annual pay is unchanged — but they are unbudgeted money if you plan monthly against two checks. On a $65,000 salary that's $5,000.00 a year arriving in two lumps.
From the public test suite
assert biweeklyPay($65,000).semimonthly == 2,708.33 ✓
assert biweeklyPay($100,000).biweekly == 3,846.15 ✓
// 36 cases · 96 assertions · runs on every deploy — see all
Sources
Pure algebra — this tool needs no jurisdiction data. The formula and its public test cases are the source.
Built and maintained by Ethan Chen, independent developer. No credential is claimed that we don't have — what this page offers instead is a published formula and a public test suite.