Per Diem Calculator
Four nights is five days, two of them travel days.
Work out Per Diem. Four nights is five days, two of them travel days. Counts the thing everyone forgets to count.
The share of the daily rate paid on the first and last day
Total per diem
937.50
4 nights, 5 days · 187.50 a day on average
A trip of four nights spans five days, and the first and last are travel days at a reduced rate under most schemes. Lodging is paid per night and meals per day, so counting both the same way is the standard error — it either adds a night that never happened or drops a day of meals.
How the Per Diem Calculator works
Lodging, meals and incidentals for a trip, with the first and last day prorated at the travel-day rate. Lodging is paid per night and meals per day, and counting both the same way is the error that makes per diem claims wrong.
Also known as: business travel allowance calculator · meals and incidentals per diem · how much per diem for a trip · travel day proration calculator
Nights and days are counted differently
Lodging is paid per night and meals per day, and a trip of four nights spans five days. Counting both the same way is the error that makes per diem claims wrong — it either invents a night that never happened or drops a day of meals.
The first and last day are travel days, when you are only away for part of the day. Most schemes prorate them, commonly at 75% of the daily meals rate and sometimes at 50%. Applying the wrong proration to a two-week trip is a meaningful sum.
A same-day trip with no overnight stay has no lodging element at all and often falls below a minimum duration for any meals payment. Whether it qualifies is a scheme rule rather than arithmetic, and it is the case most likely to be claimed wrongly out of habit.
Why a flat allowance rather than receipts
A per diem exists to avoid processing receipts for small predictable costs. The trade is deliberate: you keep the difference if you spend less and absorb it if you spend more, and in exchange nobody itemises a sandwich. That is what makes the scheme administratively cheap.
Because it is a flat allowance rather than a reimbursement, staying within the published rate usually keeps it untaxed. Amounts above the published rate are generally treated as taxable income, which is why generous employers tend to run the excess through payroll rather than through expenses.
Lodging is commonly handled differently, on actual cost up to a cap, because hotel prices vary too much to flat-rate sensibly. That mixed treatment — flat rate for meals, actual for lodging — is the most common structure and the reason receipts are still needed for part of a trip.
Where the rates come from
Government agencies publish per diem schedules by city and often by season, and private employers widely adopt them because staying within a published rate keeps the payment untaxed. They are revised at least annually and sometimes more often for volatile destinations.
International rates vary enormously and using a domestic rate abroad leaves staff genuinely out of pocket in expensive cities. Using a foreign city rate domestically has the opposite problem and creates a taxable benefit, so the destination-specific figure matters in both directions.
The defaults on this page are illustrative and should be replaced with the current published rate for the destination. That is the same principle applied elsewhere in this cluster: a rate that changes annually does not belong hard-coded into a calculator that will be read next year.
Where to go next
The Per Diem question rarely arrives on its own. These are the ones that usually come with it:
- Mileage Reimbursement Calculator — The rate covers depreciation, not just fuel.
- Take Home Pay Calculator — Bands are inputs, because they change every year.
- Day Rate Calculator — Billable days top out near 220, not 260.
- Loan & EMI Calculator — Monthly payment, total interest, and a full amortization schedule.
Not financial advice. This calculator is for planning and illustration, not financial advice. Real products carry fees, taxes, and terms it does not model. Confirm figures with your lender or a qualified adviser before committing.
Frequently asked questions
How is per diem calculated?
Lodging by the night, meals and incidentals by the day, with the first and last day usually prorated. A four-night trip spans five days: three at the full rate and two travel days at a reduced one.
Why are travel days paid at a lower rate?
Because you are only away for part of them. Most schemes use 75% of the daily meals rate on the day of departure and the day of return, though some use 50%.
Is per diem taxable?
Generally not, if it stays within the published rate for the destination and the trip is properly documented. Amounts above the published rate are usually treated as taxable income.
Do I need receipts for per diem?
That is the point of a per diem — meals and incidentals are paid at a flat rate without receipts. Lodging is often reimbursed on actual cost up to a cap, so those receipts usually are needed.
What counts as incidentals?
Tips, laundry, and small unavoidable costs of being away. It is a small daily amount and it is deliberately not itemised, which is what keeps the scheme administratively cheap.
Where do per diem rates come from?
Government schedules publish them by city and season, and they are revised at least annually. Enter the current rate for your destination — the defaults here are illustrative only.
What is the difference between per diem and expense reimbursement?
Per diem is a flat allowance paid without receipts; reimbursement pays actual documented costs. Many schemes combine them — per diem for meals and incidentals, actual cost for lodging and travel.
Do I keep the difference if I spend less than the per diem?
Under a genuine per diem scheme, yes — that is what makes it administratively cheap. It is also why schemes cap the rate rather than paying actuals.
Are international per diem rates different?
Substantially, and they are published by city and often by season. Using a domestic rate for an expensive foreign city leaves employees out of pocket and using a foreign rate domestically creates a taxable benefit.
What if my employer pays above the published rate?
The excess is generally treated as taxable income in most systems. Employers who pay generously usually run the excess through payroll rather than through expenses for exactly this reason.
Does per diem apply to a day trip?
Often only above a minimum duration or distance, and usually at a reduced meals rate with no lodging element. A trip with no overnight stay has no nights to pay for.
Who sets per diem rates?
Government agencies publish schedules that private employers commonly adopt, because staying within a published rate keeps the payment untaxed. They are revised at least annually.
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