Build a cTrader session indicator from plain rules

A typical session indicator divides the 24-hour trading day into the three major global sessions: Asian (Tokyo/Sydney), London (European), and New York. It draws a semi-transparent rectangle from the session start time to the session end time, with the rectangle height spanning the session high to low price.

Some session indicators also draw horizontal lines extending from the session high and low into the following session. These lines can serve as reference levels for breakout or reversal strategies based on prior session ranges.

Session boundaries depend on your trading convention. Common definitions use UTC or a specific financial center time zone. For example, you might define the London session as 08:00 to 16:30 London time, which shifts by one hour during daylight saving transitions.

When requesting a session indicator, specify the exact start and end times for each session, the reference time zone, and whether the indicator should account for DST changes. The cTrader Algo API provides Server.TimeInUtc for server time, and you can use .NET TimeZoneInfo for converting between zones.

cTrader Algo provides chart drawing objects that session indicators commonly use. Chart.DrawRectangle creates a named rectangle between two time-price points, which works for session boxes. Chart.DrawHorizontalLine draws a price level across the chart for session high/low projections. Chart.DrawText adds labels to identify each session.

For time calculations, the indicator reads Bars.OpenTimes to identify which bars fall within a session. Server.TimeInUtc gives the current server time in UTC. Standard .NET TimeZoneInfo handles conversions and DST transitions when the session times are defined in a local time zone.

Before building a custom indicator, check whether cTrader built-in features cover your needs. The status bar shows currently active sessions. The Active Symbol Panel displays trading schedules and countdown timers. The MarketSessions API exposes Sydney, Tokyo, London, and New York objects with IsOpen, StartTime, and EndTime properties.

A custom indicator adds visual session boxes on the price chart, configurable display options, and extended session-range lines that the built-in features do not draw. If you need those visual elements, a custom indicator is the right tool.

Pineify checks the generated source for compiler and cTrader API diagnostics. A clean result means no reported compile errors under the supported reference. It does not verify that your session times match reality or that session-range levels will produce useful signals.

Review the time zone logic, session boundaries, and drawing code before copying the source into cTrader. Add the indicator to a chart and compare the drawn rectangles against known session times on the symbols you trade.