Backorder Rate

A demand-fulfillment pain KPI. Lower is better. Distinct from fill rate (which measures quantity shipped vs ordered).

Backorder % = backordered lines ÷ total lines × 100.

Tip: Keep “Backordered Lines” and “Total Order Lines” on the same basis (units, period, and definition) before you calculate.

Cluster: Logistics hub · OTIF rate · Business hub · Percentage guide

Backorder rate is the share of order lines (or units) that could not ship complete and were backordered.

Enter backordered lines and total order lines for the same period.

Lines placed on backorder
All order lines in the period

Backorder Rate

Understanding Backorder Rate

How we calculate. Backorder % = backordered lines ÷ total lines × 100. See our methodology and accuracy policy .

Real-world scenario: A typical Backorder Rate case uses backordered lines 150 and total order lines 5000. Enter the same figures below to reproduce the worked path.

What is Backorder Rate?

A demand-fulfillment pain KPI. Lower is better. Distinct from fill rate (which measures quantity shipped vs ordered).

  • Line or unit basis—stay consistent
  • Same period as order volume
  • Lower is better

The Formula

Backorder Rate
Backorder % = (Backordered lines ÷ Total order lines) × 100

Worked Example

Scenario: 150 backordered lines out of 5,000 total lines.
Step 1: 150 ÷ 5000 = 0.03
Step 2: × 100 = 3%
Answer: Backorder rate is 3%.

Common Use Cases

  • Inventory health: stockout impact
  • Customer service: incomplete orders
  • S&OP: supply gaps

Pro Tips

  • Segment A-items
  • Don’t mix cancelled demand
  • Pair with fill rate
ScenarioWhen to use
Percent of a numberFinding a part of a whole (tax, tip, score)
Percent changeComparing old vs new values

Limitations: Backorder Rate results are educational logistics and supply-chain planning aids—not SLAs, carrier contracts, or inventory valuation advice. Confirm definitions with your WMS/TMS and finance policies.

Common mistakes

  • Swapping part and whole: The denominator must be the full total, not a subset.
  • Rounding too early: Carry extra decimal places through multi-step work before rounding the final percent.
  • Mixing percent and decimal forms: Enter rates in the format the calculator labels expect.

The worked example for backorder rate was verified with the calculator form on this page—enter the same values to confirm the result.

When to use this calculator

  • Use this page when your wording matches backorder rate and the form labels on screen.
  • Use percent of a number for “what is X% of Y?” problems.
  • Use number is what percent when you know part and whole and need the percent.

Still unsure about backorder rate? Start with the quick answer above, then open the linked calculator that matches your wording.

Frequently Asked Questions

How do I use this backorder rate calculator?

For backorder rate (percentage calculator), enter the values labeled on the form, then press Calculate. Compare the result to the worked example on this page.

What formula does this page use?

See the quick answer and formula box above for backorder rate—the same percentage calculator expression is applied to your inputs.

What if my result looks wrong?

When checking backorder rate, re-check part vs whole (or rate vs base), rounding, and whether percents were entered as 25 rather than 0.25 when the form expects percents.

Authoritative References

For logistics and supply-chain KPI definitions, consult:

  • CSCMP — supply chain management resources
  • ASCM / APICS — operations and inventory body of knowledge
  • ISO 28000 — security management for the supply chain (context)