Minimum Bid Increment Algorithm


How minimum bid increments are calculated

Bid Amounts and Minimum Bid Increments

Starting Bids

Items are added to the auction with a "minimum starting bid", which is set by the auction's administrator(s). The first bid on the item must be equal to or greater than this starting bid value.

Minimum Bid Increments

In order to keep bidding fair, the next bid on an item must be greater than or equal to the "Minimum Bid". The minimum bid is calculated as the sum of the current bid plus a pre-determined incremental amount (the minimum bid increment). The following algorithm is used to calculate the next minimum bid amount:

Minimum Bid Increment Algorithm
When The Current Bid IsThe Minimum Bid Is
$0.00The Minimum Starting Bid
Between $0.01 — $0.99Current Bid + $0.05
Between $1.00 — $2.49Current Bid + $0.10
Between $2.50 — $4.99Current Bid + $0.25
Between $5.00 — $9.99Current Bid + $0.50
Between $10.00 — $24.99Current Bid + $1.00
Between $25.00 — $49.99Current Bid + $2.50
Between $50.00 — $99.99Current Bid + $5.00
Between $100.00 — $249.99Current Bid + $7.50
Between $250.00 — $499.99Current Bid + $10.00
Between $500.00 — $999.99Current Bid + $25.00
Between $1,000.00 — $2,499.99Current Bid + $50.00
Between $2,500.00 — $4,999.99Current Bid + $75.00
Between $5,000.00 — $9,999.00Current Bid + $100.00
Between $10,000.00 — $24,999.99Current Bid + $250.00
$25,000.00 and upCurrent Bid + $500.00

Regardless of the currency used by the auction, the numerical increments outlined above are the same.

This algorithm is similar to those found on commercial auction sites such as eBay™.