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McClellan Oscillator: Breadth Momentum (EMA19 − EMA39 of Net Advances)

The classic breadth-momentum gauge: the 19-day EMA of net advances minus the 39-day EMA, computed across roughly 4,750 eligible US common stocks in a typical session. Positive = participation accelerating; negative = decelerating. Zero-line crosses, extremes, and divergences against SPY are the signals — and a negative reading is one of the four Hindenburg Omen criteria.

Today's reading

As of market close on September 4, 2026, the McClellan Oscillator is -7.61 — short-term breadth (19-day EMA of net advances) is lagging intermediate breadth (39-day EMA) across roughly 4,750 eligible US stocks in a typical session. The oscillator rose 4.4 points from the prior session. The series runs from 2010 to present.

Sources, methodology & freshnessLast updated 2026-09-04 · Open ↓
Source
Daily net advances across eligible US common stocks (roughly 4,750 in a typical session; 2010–present)
Methodology
EMA19 − EMA39 of raw net advances; EMAs SMA-seeded after a full warmup period
Updates
Daily after market close (~1:30 PM PT)Last: 2026-09-04
Maintained & reviewed by Yuriy Matso — methodology shown on the page.
Breadth momentum2026-09-04 · close
DECELERATING
-8

Short-term breadth is lagging intermediate breadth.

Oscillator
-7.61
Δ 1 Day
+4.4
Zero Line
below

SPY closed at $770.19. A negative oscillator is one of the four Hindenburg Omen criteria.

Range:
01

McClellan oscillator

McClellan Oscillator vs SPY

EMA19 − EMA39 of ratio-adjusted net advances — RANA = 1000 × (advances − declines) ÷ (advances + declines) — with SPY overlaid. Ratio adjustment is what keeps a reading in 2011 comparable to one today while the universe roughly doubled. Judge extremes against this series' own history (±60 marks stretch), not classic NYSE thresholds. The universe here is broad US common stocks rather than the NYSE composite.

McClellan OscillatorSPY price (right)Zero line
02

Summation index

McClellan Summation Index vs SPY

The running total of the oscillator — the same construction StockCharts publishes as NYSI, computed on our universe rather than the NYSE composite, so it is not $NYSI and the two will not agree. It accumulates from the first scored session in 2010, which makes it an index rather than a level: read its direction, its zero crossings and its divergences against price, never its absolute value.

Summation IndexSPY price (right)Zero line
03

NYSE-listed

NYSE-listed oscillator and summation index

The McClellan pair computed on NYSE-listed common stocks — our analogues of the $NYMO and $NYSI series other charting packages carry. They are deliberately not those tickers: $NYAD counts every NYSE-listed issue, and roughly half are ETFs, preferreds, closed-end funds, rights and warrants rather than operating companies. The cumulative NYSE advance-decline line — the $NYAD analogue itself — lives on the A-D Line page, because an advance-decline line is not a McClellan indicator.

NYSE-listed oscillator (-13.3)SPY price (right)
NYSE-listed summation index (709)SPY price (right)
04

Nasdaq-listed

Nasdaq-listed oscillator and summation index

The same pair on Nasdaq-listed common stocks — the $NAMO and $NASI analogues, with the same caveat. Venue resolves for 99.3% of directional issues; anything that is neither exchange is counted in neither series, so NYSE-listed and Nasdaq-listed do not sum to the whole-universe index above.

Nasdaq-listed oscillator (-2.5)SPY price (right)
Nasdaq-listed summation index (543)SPY price (right)

Read the venues against each other. One rolling over while the other holds is a rotation rather than a market-wide deterioration. Today the NYSE-listed summation sits at 709 and the Nasdaq-listed at 543.

Reading the current tape

As of 2026-09-04, the McClellan Oscillator stands at -7.61 — breadth momentum is negative (short-term participation decelerating), with SPY at $770.19. The oscillator rose 4.4 points on the session.

How McClellan Oscillator Works

  1. 1
    Start from daily net advances
    Each session we count advancing minus declining eligible US common stocks — roughly 4,750 in a typical current session — using the same series that drives the advance-decline line.
  2. 2
    Smooth with two exponential moving averages
    The oscillator is the 19-day EMA of net advances minus the 39-day EMA. Both EMAs warm up over their full period (seeded with the SMA) before the oscillator prints, so early values are never seed-dominated.
  3. 3
    Read it as breadth momentum
    Positive = short-term breadth running ahead of intermediate breadth (acceleration); negative = deceleration. Zero-line crosses mark momentum regime changes; extremes mark exhaustion.
  4. 4
    Watch divergences and the zero line
    A rising index with a falling oscillator means each push is coming on weaker participation. A deeply negative oscillator that turns up before price does is the classic early-bottom tell. The oscillator is also criterion #3 of the Hindenburg Omen (must be negative).

Who Uses McClellan Oscillator

Swing Traders
Time entries within trends: oscillator pullbacks to/below zero inside a healthy uptrend are reset points; the curl back up is the trigger.
Mean Reverters
Deep negative extremes mark short-term selling exhaustion; deep positive extremes after extended rallies flag chase risk.
Trend Followers
Use sustained time on one side of zero as a regime read: persistent positive readings characterize durable advances, persistent negative ones distribution phases.
Omen Watchers
The Hindenburg Omen requires a negative McClellan reading. Track it here to see how close the breadth-momentum leg of that signal is to flipping.

Pro Tips

01
Complex vs simple structures
The McClellans' own reading style: a "complex" bottom (multiple oscillator troughs below zero) carries more durable-low information than a single V-shaped dip. Same for tops in mirror image.
02
Divergence at the extremes is the strongest form
Price making a lower low while the oscillator makes a higher low (still negative) is the textbook positive divergence — breadth momentum improving before price.
03
Mind the scale of our variant
We compute raw net advances over roughly 4,750 eligible common stocks in a typical session, so amplitudes run larger than the classic NYSE ratio-adjusted oscillator. Compare readings to this chart's own history, not NYSE-based thresholds.
04
Pair with the A-D line
The oscillator is the momentum of the A-D line. Oscillator says "how fast breadth is changing"; the cumulative line says "where breadth stands". Signals agreeing across both are the high-conviction ones.

Common Issues & Solutions

Your values differ from StockCharts / the McClellan Financial site▾
Variant differences: the classic oscillator uses NYSE-only issues and often ratio-adjusted net advances. Ours uses raw net advances across eligible US common stocks — roughly 4,750 in a typical session — so read levels against this series' own history.
The oscillator whipsaws around zero▾
Normal in range-bound tape — breadth momentum genuinely flips frequently when the market chops. The zero-cross signal works best when it confirms a breakout or follows an extreme; standalone crosses in quiet ranges are noise.
How do I read the Summation Index?▾
It accumulates from an arbitrary start, so its LEVEL means nothing on its own — read direction, zero crossings and divergence against price. The NYSE-listed and Nasdaq-listed variants stand in for NYSI and NASI, but count common stocks only rather than every listed issue, so they will not match those tickers.

Frequently Asked Questions

What is the McClellan Oscillator?▾
A breadth-momentum indicator developed by Sherman and Marian McClellan in 1969: the 19-day EMA of net advances (advancing minus declining stocks) minus the 39-day EMA. Positive readings mean short-term breadth is outrunning intermediate breadth — participation accelerating; negative readings the reverse.
How do I read the zero line?▾
Zero crossings mark breadth-momentum regime changes. Crossing up through zero after a negative extreme is an early-recovery signal; persistent time below zero characterizes corrections and distribution phases. The Hindenburg Omen requires the oscillator to be negative as one of its conditions.
What counts as overbought or oversold?▾
For the classic NYSE ratio-adjusted oscillator, ±70 to ±100. Our variant uses raw net advances over roughly 4,750 eligible common stocks in a typical session, so amplitudes are larger — judge extremes against this chart's own history. Extremes can flag exhaustion or an initiation thrust; context matters.
What is a McClellan divergence?▾
Price and the oscillator disagreeing at the swing: index lower low + oscillator higher low = positive divergence (breadth momentum improving first, common at bottoms); index higher high + oscillator lower high = negative divergence (advance narrowing, common before corrections).
How is this related to the Summation Index?▾
The McClellan Summation Index is the running cumulative total of the oscillator — a slower, position-style indicator built on the same engine. We publish it, with NYSE-listed and Nasdaq-listed variants alongside the whole-universe series.
What universe and parameters does this use?▾
Net advances across eligible US common stocks (roughly 4,750 in a typical session; 2010–present), EMA19 − EMA39 with full-period SMA-seeded warmup, recomputed after every close. This is a broad-universe raw-net-advances variant. It differs from the NYSE-only ratio-adjusted version.

Explore Other Tools

Advance-Decline Line
The net-advances series this oscillator is built from
Hindenburg Omen
Uses a negative McClellan as one of its four criteria
MA Breadth
% of stocks above the 10/50/100-day moving averages
New Highs – New Lows
52-week breadth balance across the full universe
Last updated: 2026-09-04