Inventory, demand & supply planning · Core
Days inventory outstanding
Also called: DIO, inventory days
ELI5
An estimate of how many days inventory is held before sale or use.
Used in conversation
“The number is useful only if everyone calculates days inventory outstanding the same way.”
Pitch context
You will see “Days inventory outstanding” in operating plans, procurement packs, supplier reviews and supply-chain reports when the discussion reaches inventory, demand & supply planning.
Why it matters: In inventory, demand & supply planning, different calculation boundaries, periods or accounting treatments can change the number and the decision.
Caution
Calculation, recognition and disclosure can vary by accounting framework, company policy and reporting context.
Sources & evidence · 7
Direct term-level sources and supporting source families.
- IFRS Foundation — IFRS GlossaryDirect source · primary · checked 2026-08-16
- U.S. Small Business Administration — Break-even pointDirect source · primary · checked 2026-08-16
- U.S. Bureau of Labor Statistics — Productivity programmeDirect source · primary · checked 2026-08-16
- Financial Accounting Standards Board — FASB Accounting Standards CodificationSupporting source family · primary · checked 2026-08-16
- U.S. Securities and Exchange Commission — Non-GAAP Financial Measures — Compliance and Disclosure InterpretationsSupporting source family · primary · checked 2026-08-16
- U.S. Acquisition.gov — Federal Acquisition Regulation Part 15 — Contracting by NegotiationSupporting source family · primary · checked 2026-08-16
- UK Government — Groceries Supply Code of PracticeSupporting source family · primary · checked 2026-08-16