Volume Delta Indicator on Bitcoin

What it shows

A histogram in its own pane under the price, one bar per candle, drawn from a zero line. Green bars rise above zero, red bars drop below it. The height is the size of the difference in volume units, so a tall bar means one side clearly outweighed the other.

How Pravex works it out

Split each candle’s volume into buying and selling. When the feed carries taker-buy volume (the part of the candle bought by market orders), that is the buying volume, held between zero and the candle’s total volume, and selling is whatever is left.
When a candle has no taker split, the whole volume goes to one side by direction: buying if the candle closed above its open, selling if it closed below. A candle that opened and closed at the same price follows the change from the previous close, and if that is level too it keeps the side of the previous candle. Missing volume counts as zero.
Delta is buying volume minus selling volume. Pravex draws it as a bar from zero to the delta, green when it is above zero and red otherwise, with a level line at zero.

Settings

Setting	Default	What changing it does
How candles are grouped	Time (greyed out)	Shown greyed out in the app and not used. Pravex does not scan a lower timeframe to rebuild the split; it takes buying and selling straight from each candle, so this choice would change nothing.
Scan a chosen timeframe	off (greyed out)	Greyed out for the same reason. There is no lower-timeframe pass for a chosen timeframe to feed.
Timeframe	1 minute (greyed out)	Greyed out too, and only shown once the box above it is ticked. The code never reads it.

How traders read it

Read the sign and the size together. A tall green bar says buyers dominated that candle. A run of shrinking green bars while price keeps rising says the push is getting less support. With invented numbers: three candles show +120, +40 and +25 in a row: price may still be climbing, but the buying behind each step is smaller.

The interesting case is disagreement: a candle that closes up while the delta is negative, or the reverse. It means market sellers hit more volume than market buyers even though price rose. That mismatch can only appear when the feed carries a real taker split, which the bitcoin chart on this page does not.

When it misleads

On this page the split is a rule, not a measurement. Hyperliquid candles carry volume but no taker split, so every up candle gets a positive delta and every down candle a negative one. The sign simply repeats the candle colour and only the size adds anything, so treat it as volume coloured by direction. Where a feed does carry taker-buy volume, Pravex uses it and the bars can disagree with the candle, which is where delta earns its place. Even then it is the net of a whole candle, not the order flow inside it. Spot gold has no exchange volume, so there is nothing to split.

Questions and answers

What does a green or red Volume Delta bar mean?

Buying volume minus selling volume for each candle. Above zero means buyers had more of the candle’s volume, below zero means sellers did.

How does Pravex split buying from selling volume?

With the taker-buy volume when the feed has it. Without it, the whole candle goes to buying if it closed up and selling if it closed down. The bitcoin chart here has no taker split, so it uses the direction rule.

Can Volume Delta be negative on a green candle?

Only with a real taker split. On this page every up candle is counted as buying, so its delta is positive.

Is Volume Delta the same as plain volume?

No. Volume is the total traded. Delta is the difference between the buying and selling parts of it, so it can be negative.

Why is Volume Delta drawn on bitcoin and not gold?

Spot gold carries no exchange volume, and delta needs volume to split. Bitcoin from Hyperliquid has it.