Why the same chart on two platforms looks different

[Shadow Trader]

Open the same pair and timeframe in two different platforms connected to the same broker. The candles may not match exactly. Highs and lows differ by a point or two, and some bars look different in shape.

Several reasons. Platforms receive the quote stream with slightly different timing, so a tick that falls near a bar boundary lands in different bars. Some platforms drop ticks to save bandwidth. Others build bars from a data server's own history instead of local ticks.

Time zone settings also differ. A one-hour bar starting at 10:00 in one platform might start at 10:00 in another's time zone, which is offset by 30 minutes or an hour for some zones. Daily bars are especially vulnerable, since the "day" can begin at midnight server time, at 5pm New York, or at some other time.

For strategies using levels like the previous day's high and low, the definition of "day" changes the numbers.

When combining signals from a charting service and execution on a broker platform, a mismatch of a pip or two is normal. It becomes a problem when the strategy depends on exact levels.

How different are the bars between your charting software and your broker's platform?

[Amanhasnoname]

I chart on a separate service and execute on my broker's platform, and the difference used to bother me more than it should have. On a typical day the one minute highs and lows differ by a point or two, which I can live with. The real trouble came with daily levels, because my charting tool started the day at midnight in my local time and the broker platform started it at five in the afternoon New York time.

That meant the previous day's high I was trading around was a completely different number on each screen for a while. I lost a couple of trades waiting for a reaction at a level that the market wasn't paying attention to before I worked out what was going on.

Now I set both to New York close and I take the actual level from the broker platform, since that is the price that fills me. The charting service is only for the bigger picture.