30m, or 30 Minutes, represents data collected over 30 minutes plotted as a single data point.

In crypto trading, and charting specifically, 30 Minutes is a common time frame used by traders to review a digital asset’s price movements plotted in 30-minute intervals over some specific time period.

Each bar, candle, or column would represent price action for a specific 30 minutes.

If we were to look at a single day on a chart for example, which is made up of 24 hours, we would see 48 bars or candles plotted on that chart – 2 for every hour X 24 hours = 48 bars or candles.

The 30-minute time frame can be used as part of a more complex multi-time frame strategy, such as using the 5-minute, 30-minute and 4-hour time frames together,  determining trend using the 4hr, and then setting trade entries and exits using the lower time frames.