What it is
Bill Williams argued that the speed of momentum changes before momentum itself, which changes before price. AC is his measure of that first change. It is drawn as a histogram: bars coloured green when higher than the previous bar and red when lower.
It has no settings to tune: its lengths (5 and 34 for the Awesome Oscillator, 5 for the smoothing) are fixed by the method.
How it is calculated
1. Take the median price of each candle, (high + low) / 2. 2. Awesome Oscillator (AO) = 5 period simple moving average of median price minus the 34 period one. 3. Take a 5 period simple moving average of AO. 4. AC = AO minus that 5 period average.
How to read it
How to trade it
- 1
Williams' rule: above 0, two rising (green) bars in a row is enough for a buy; below 0, you need three rising bars because you are buying against the current momentum.
- 2
Use it with the trend, for example on a 15 minute US30 chart above its 50 EMA, taking only the buy setups.
- 3
Enter on the close of the candle that completes the green bar sequence.
- 4
Stop below the most recent swing low, for example 30 to 50 points on US30.
- 5
Exit when AC prints two falling bars above 0, or at 2 times the stop.
The buy is cancelled if AC prints a falling bar straight after entry and price closes below the signal candle's low.
WickSpeak writes a plain-English reading of the Accelerator Oscillator on the live candle: what it is, whether momentum is speeding up or slowing down now, how traders use that and what would prove it wrong. In Playbook, a condition can check when AC crosses above or below zero, stays above or below zero, or is rising or falling.
Best markets and timeframes
Works on any market. On gold and indices it is most useful on 5 minute to 1 hour charts as a timing aid within a trend. On its own it gives too many signals to trade.
Common mistakes
- Using it as a stand-alone entry. It is a warning light for momentum, not a full system.
- Reading a falling bar above 0 as a sell. It only means the rise is slowing.
- Confusing it with the Awesome Oscillator. AC is the change in AO, so it turns earlier and more often.
Works well with
Questions traders ask
What is the Accelerator Oscillator?
It is Bill Williams' measure of whether momentum is speeding up or slowing down. It is the Awesome Oscillator minus a 5 period average of the Awesome Oscillator.
What are the Accelerator Oscillator settings?
It uses fixed lengths of 5 and 34 for the Awesome Oscillator and 5 for the smoothing. Most platforms, including WickSpeak, do not offer settings.
What is the difference between the Awesome Oscillator and the Accelerator Oscillator?
The Awesome Oscillator measures momentum. The Accelerator measures how fast that momentum is changing, so it turns sooner but gives more signals.
What do green and red bars mean on AC?
A green bar is higher than the previous bar and a red bar is lower. The colour shows the direction of change, not whether the reading is above or below 0.