Safety stock: Definition, Formula & Why It Matters

Also called: Buffer stock

Safety stock is extra inventory held as a buffer against demand spikes or supplier delays. It is your insurance against stockouts during the lead-time window. Too little risks running out; too much ties up cash.

Safety stock formula

Safety stock = (max daily sales × max lead time) − (avg daily sales × avg lead time)

Example

When demand or lead times can spike, safety stock covers the gap between worst-case and average usage.

Why it matters for Reverb sellers

For sellers with variable demand or long overseas lead times, the right safety stock is the difference between reliably in stock and frequently sold out. It is a deliberate trade-off between availability and tied-up capital.

How Verbstack helps

Verbstack tracks demand variability so you can size safety stock to your actual sales pattern.

Track this on every order, automatically.

  • Real fees, margins, and profit on every Reverb sale
  • COGS and inventory tracked for you, no spreadsheet
  • Full history and a live monthly P&L
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See this number on every order.

Connect your Reverb shop and Verbstack tracks your fees, margins, and profit automatically.

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