Per Diem Allowance Calculator (GSA Federal Rates)
Calculate a federal travel per diem from lodging and M&IE rates and trip length, applying the GSA 75% first/last-day rule. Editable rates — verify on GSA.gov. Runs in your browser.
2 nights lodging
2025 std CONUS $110. Look up locality on GSA.gov.
2025 std CONUS $68.
US federal per-diem (GSA) = lodging per night + meals & incidental expenses (M&IE) per day, with the first and last travel day reimbursed at 75% of M&IE. Rates are locality-specific and set annually — the defaults here are the 2025 standard CONUS rates ($110 lodging, $68 M&IE); look up your exact city/county and the current fiscal-year rate at GSA.gov (or DoD/State for OCONUS and foreign travel). Lodging excludes taxes (often reimbursed separately). Educational; everything runs in your browser.
About this tool
Per diem is a fixed daily allowance that covers lodging and meals while traveling for work, used instead of reimbursing actual itemized receipts. In the United States, the General Services Administration (GSA) publishes official per-diem rates for federal travel within the continental US (CONUS), and these rates are widely adopted by private employers too. A per diem has two parts: a lodging rate (a maximum per night, excluding taxes) and an M&IE rate (meals and incidental expenses per day). This calculator combines them with trip length to total the allowance, and it applies the key GSA rule that trips up people doing the math by hand: the first and last calendar day of travel are reimbursed at only 75% of the full M&IE rate, because you're not traveling for the entire day on either end. So a three-day trip pays full M&IE for the one middle day and 75% for the first and last, while lodging is paid for the nights actually spent away (one fewer than the number of travel days). The rates themselves are locality-specific — major cities have higher lodging caps than the standard rate — and they're updated every federal fiscal year, so the calculator ships with the 2025 standard CONUS figures ($110 lodging, $68 M&IE) as editable defaults and prompts you to look up your specific destination and the current rate on GSA.gov (the Department of Defense and State Department set the equivalent rates for non-foreign OCONUS and foreign locations). Lodging taxes are typically reimbursed separately from the per-diem lodging cap in many jurisdictions. Use this to estimate a travel allowance or check an expense report; confirm the exact locality rate before relying on it. Educational; everything runs in your browser; nothing is uploaded.
How to use it
- Enter the number of travel days (lodging nights are one fewer).
- Enter the lodging rate per night and the M&IE rate per day for your destination (look them up on GSA.gov).
- The tool applies 75% M&IE to the first and last day automatically.
- Read the total allowance with the lodging and M&IE breakdown.
Frequently asked questions
- How is per diem calculated?
- Lodging rate × nights, plus M&IE per day with the first and last travel day at 75%. For a 3-day trip: lodging × 2 nights + (1 full M&IE day + 2 × 75% M&IE days).
- Why are the first and last days only 75%?
- GSA reimburses M&IE at 75% of the daily rate on travel days because you are not away for the full day when departing or returning. Full M&IE applies only to complete days at the destination.
- What are the 2025 standard CONUS rates?
- The standard continental-US rate is $110 for lodging and $68 for M&IE per day. Many cities have higher locality rates. Rates change each fiscal year — verify the current figure for your destination on GSA.gov.
- What does M&IE include?
- Meals and incidental expenses — breakfast, lunch, dinner, and small incidentals like tips. It is a flat daily amount regardless of what you actually spend, which is the point of a per diem.
- Does the lodging rate include taxes?
- No. The GSA lodging rate is a pre-tax nightly cap; lodging taxes are commonly reimbursed separately from the per-diem amount. Check your organization's policy.
- Is anything uploaded?
- No. All calculations run entirely in your browser; rates are editable so you can match your locality.