Bids and asks describe resting interest.
The bid side contains displayed buy orders; the ask side contains displayed sell orders. The highest bid and lowest ask are the best visible prices. A new aggressive sell can meet bids, while an aggressive buy can meet asks. The book is specific to an exchange and instrument.
A BTCUSDT Spot book and a BTCUSDT perpetual book are different markets, even when their labels and prices look similar. Their quantities, account requirements and settlement can differ. Check the market category before comparing their depth.
Calculate the spread first.
In a fictional snapshot, the best bid is 49,990 USDT and the best ask is 50,000 USDT per BTC. The spread is 10 USDT. Their midpoint is 49,995 USDT, so the spread is approximately 0.0200% of midpoint.
The midpoint is an arithmetic reference, not an executable quote. An immediate buy normally starts at the ask, while an immediate sell starts at the bid. A spread percentage should state its denominator; two interfaces can display different percentages if they use different conventions.
Read level size and cumulative size separately.
Use the following fictional ask side. Each quantity is additional BTC at that price; cumulative quantity includes the earlier rows.
| Price, USDT per BTC | BTC at this level | Cumulative BTC |
|---|---|---|
| 50,000 | 0.010 | 0.010 |
| 50,010 | 0.015 | 0.025 |
| 50,030 | 0.020 | 0.045 |
A cumulative value of 0.025 BTC at 50,010 does not mean 0.025 BTC is offered at that single price. It combines 0.010 at 50,000 and 0.015 at 50,010. The market-order example shows how consuming several levels changes the average fill.
If a panel shows quote notional instead, the values must incorporate price. The entire three-level ask snapshot represents 2,250.75 USDT of displayed notional. Base quantity and quote value should not be compared as though they were the same unit.
A depth chart is another view of the same snapshot.
A cumulative depth path adds size as it moves away from the best price. Grouped bars can combine several price levels into a wider bucket. Changing grouping changes the shape without proving that liquidity appeared or disappeared.
In Schizo, aggregate overlays may be aligned or scaled for comparison. Such an overlay is not a tradable consolidated quote. Use the actual selected venue and instrument when assessing an order’s price and size.
Displayed size is not a completed trade.
Resting orders can be cancelled or modified before another instruction reaches them. A large visible level does not prove future support, resistance, intention or a fill. Public trade data describes completed matching; the order book describes exposed resting orders.
Feeds also have coverage limits. Bybit’s documented public order-book response omits RPI orders. A finite depth snapshot, a delayed feed and a comparison overlay each answer a narrower question than “all liquidity everywhere.”
When the book stops updating, check connection status and feed freshness before interpreting an unchanged shape. Keep the order book, chart and order status visible together, with readable units and the intended account selected.