Summary
Buy/Sell Ratio compares the visible bid-side quantity with the visible offer-side quantity in the Orderbook.
How to Calculate it
Buy/Sell Ratio = Total Visible Bid Volume ÷ Total Visible Offer Volume
How to read it
A higher buy-side share means more displayed quantity is currently on the bid side, while a higher sell-side share means more is on the offer side. Treat the measure as a snapshot of visible interest rather than a prediction of the next price move.
Things to keep in mind
The ratio changes with the displayed levels and can be distorted by one large order. It does not include hidden interest or guarantee that displayed orders will remain available.