Credits and licences
Last updated 2026-10-24
Our own code
The calculators and page layouts are written for this site. The pages make no requests to other servers except to this site’s own rate files and, if you use the Pro email box, to this site’s own waitlist address. No library, font or script from another party is used.
Third-party material
No code libraries. The rates come from the official data sets below; all of them are public-domain or freely reusable official works. The Sources and dates page gives the effective date, expiry and last-checked date of each.
| Name | Used for | Licence |
|---|---|---|
| GSA per diem rates, FY2026 and FY2027 (flat files) | Lodging and M&IE rates for continental U.S. destinations | U.S. federal government work, public domain (17 U.S.C. 105) |
| GSA, M&IE breakdowns | Breakfast, lunch, dinner and incidentals amounts for each M&IE total | U.S. federal government work, public domain (17 U.S.C. 105) |
| IRS Publication 463 | Rules for the self-employed view (meals only, 50% limit, partial days) | U.S. federal government work, public domain (17 U.S.C. 105) |
| BMF letter of 5 December 2025 on travel costs 2026 (foreign allowances) | German Verpflegungspauschalen for 175 countries and 48 cities | Official work (par. 5 UrhG), free to reuse |