An ETH perpetual screen can show several prices at once. Reading them as interchangeable numbers makes the screen harder to understand. Last price, index price and mark price answer different questions. Before comparing two screenshots, check the instrument, the label and the time of capture. A visible difference alone does not establish an error, a trading opportunity or a reliable signal about where the market will move next.
Last price refers to the most recent completed trade in that contract. It tells you where that transaction happened. It does not promise that a new order will fill at the same level. An execution depends on the order and the liquidity available when it reaches the market. This is why a clean screenshot of one number cannot describe every condition that matters to an actual fill.
Index price provides a reference drawn from underlying spot markets. Mark price is a separate calculated reference used in futures risk calculations, including unrealized profit and loss and liquidation assessment. These labels are worth keeping visible when explaining a futures screenshot. Neither should be silently renamed last price. The exact calculation and applicable contract rules belong with the instrument being discussed.
A candle also needs context. An hourly chart and a four hour chart summarize activity over different intervals. If one screenshot uses a last price series and another uses a mark price series, their candles need not match. Identify the price series as well as the interval before comparing a wick, a close or a sudden move. The explanatory images here illustrate categories only. They are not live charts, account records or evidence of a particular trade.
A useful market note makes its evidence easy to read. State which instrument is shown, identify the price label and preserve the capture time whenever quoting a changing value. The ETH perpetual card attached to this article identifies the market context. Its changing quote is not a forecast or a substitute for those labels. Clear comparisons begin with matching definitions, then checking what each observation can actually support.
