Sources and Licenses

These are the public datasets currently used by the English tools. Each version and import date applies only to its own dataset. Source data can contain errors or become outdated; Calculator 360 produces its own derived calculations and estimates. Listing a provider does not imply its endorsement or sponsorship.

Sources currently used

BLS Consumer Price Index

U.S. Bureau of Labor Statistics (BLS) — Consumer Price Index (CPI-U), local series CUUR0000SA0. The local cache contains annual averages for 2000–2025 and a separate monthly observation for 2026; it contains no 2026 annual average. The cached release is dated September 11, 2026 (August 2026 CPI); imported September 26, 2026. Calculator 360 derives its inflation and real-value estimates from these data. Source and reuse terms: BLS API terms and citation notice.

USDA FoodData Central

U.S. Department of Agriculture (USDA) — FoodData Central, Foundation Foods release of April 30, 2026; imported September 26, 2026. The local cache selects five specific FDC IDs and uses nutrient values per 100 g for the English recipe tool. It does not represent all of FoodData Central. Source and reuse terms: USDA FoodData Central notice.

EPA GHG Emission Factors Hub

U.S. Environmental Protection Agency (EPA) — GHG Emission Factors Hub 2025, Table 2, published January 15, 2025; imported September 26, 2026. The local factors are in kg CO₂ per U.S. gallon of gasoline or diesel and estimate direct combustion only. They exclude upstream and other lifecycle emissions. Source and reuse terms: see the official EPA dataset and its notices.

EPA eGRID

U.S. EPA — eGRID2023 Summary Tables, Revision 2, released June 12, 2025; imported September 26, 2026. The local cache covers 28 grid areas and converts source output rates in lb CO₂/MWh to kg CO₂/kWh for the English electricity-related estimates. These are generation-output factors, not full lifecycle factors. Source and reuse terms: see the official EPA dataset and its notices.

OPM Federal Holidays

U.S. Office of Personnel Management (OPM) — Federal Holidays. The local snapshot, imported September 27, 2026, covers observed U.S. federal holiday dates for 2026–2028 in the Working Days Calculator. 2029 is not covered. The tool does not infer state, local, employer or school holidays. Source and reuse terms: see the official OPM notice.

Other active references and software

QR libraries

qrcode-generator 2.0.4, MIT license; jsQR 1.4.0, Apache 2.0 license according to the bundled license file. These files are served locally, without a CDN.

Software and graphics

No third-party Composer runtime package is used beyond the stated PHP extensions. Password tools use the browser's native cryptographic API without an external library. Logo, favicon, and icons are included locally; no remote font is loaded. Original code is declared proprietary in Composer.

Calculation references

ISO 8601; inch: 2.54 cm; pound: 0.45359237 kg; metric horsepower: 735.49875 W.