How to Plot Previous-Day High, Low & Key Levels in NinjaTrader 8

Which levels actually matter intraday?

You don’t need fifty lines on the chart — you need the handful the whole market references:

• Previous-day high, low and close. The boundaries and the settlement of yesterday’s auction. Price reacts to them constantly — breaks, retests, and rejections all happen here.
• Today’s live high and low. The developing range, updating as the session builds.
• The session open. Where today started — above or below it is a simple, powerful read on the day.
• The weekly and midnight opens. Higher-timeframe and ICT-style reference points that a lot of traders anchor to.

Does NinjaTrader 8 plot these already?

Partly. NinjaTrader ships a PriorDayOHLC indicator that draws the previous day’s open, high, low and close, and you can pick which of those to show. It covers the prior-day levels well.

What it doesn’t do is the rest of the set — the session open, the weekly open, the midnight open, and today’s live high and low — in one place, with consistent styling. That’s usually why traders reach for a dedicated levels indicator: one tool, all the references, styled the same way.

How to plot the full set of key levels

A reference-levels indicator draws each level automatically and keeps it updated, so you’re not redrawing lines every morning. What to look for:

• The levels you actually use — prior-day high/low/close, live high/low, and the opens — each one toggleable so the chart stays clean.
• Per-level styling — color, line style and labels you control, so the important ones stand out.
• Correct session and timezone handling, so the opens land at the right time and don’t drift across daylight saving.
• No repaint — the levels shouldn’t move after the fact.

What about weekly and monthly levels?

The same logic runs up the timeframes. The previous week’s high and low, and the previous month’s high and low, are higher-timeframe reference points that swing traders and position traders lean on the same way day traders use the prior-day levels — and even intraday traders watch them, because a prior-week or prior-month extreme is a place the whole market remembers.

NinjaTrader has basic building blocks here too — a current-week OHL indicator, for example — but for the prior week and prior month drawn cleanly, with the older ones faded so the current period stays clearest, a dedicated levels indicator is the tidier route. If those higher-timeframe levels matter to you, Weekly H/L Lines and Monthly H/L Lines plot them automatically alongside the intraday set.

How to install it

1. Download the indicator’s .zip — keep it zipped.
2. Open the Control Center → Tools → Import → NinjaScript Add-On… and select the .zip.
3. On a chart, right-click → Indicators…, add it, and switch on the levels you want.

The honest part

These levels don’t predict anything — they mark where the market has already agreed something matters, which is why price keeps reacting to them. Put the ones you use on the chart, leave the rest off, and let them be the reference points around which you make your own decisions.