ATR Position Size Calculator

Calculate position size based on ATR (Average True Range) volatility, so your stop loss adapts to market conditions.

$

Your trading account balance

%

Professional traders risk 0.5%–2% per trade

pips

Average True Range in pips for your pair

× ATR

e.g. 2 means stop is 2 × ATR away

Position Size (lots)

0.00 lots

Stop Distance (pips)

40.0 pips

Risk Amount

$100.00

Volatility Comparison

Current ATR vs 14-period high/low range

Low10 pips
Current20 pips
High30 pips
Norm

Why ATR-Based Position Sizing Works

ATR (Average True Range) measures market volatility. A high ATR means the market is moving more — your stop loss needs to be wider to avoid getting stopped out by noise. A low ATR means tighter stops are appropriate.

The problem with fixed pip stops: a 30-pip stop might work fine on a quiet EUR/USD day, but during a news event or when volatility spikes, normal market movement can exceed 50 pips. Your stop gets hit by volatility, not by a wrong direction call.

ATR-based sizing solves this: your stop distance adapts to current volatility. When volatility is high, you place a wider stop and reduce position size. When volatility is low, you tighten the stop and increase size. Your dollar risk stays constant regardless of market noise.

Real Examples

$10,000 account · 1% risk · 2× ATR stop

Low Volatility
PairATR=10
Stop Loss20 pips
Position Size0.50 lots
Risk Amount$100
Normal Volatility
PairATR=20
Stop Loss40 pips
Position Size0.25 lots
Risk Amount$100
High Volatility
PairATR=40
Stop Loss80 pips
Position Size0.13 lots
Risk Amount$100

Common Mistakes

#1: Fixed Stop in Volatile Markets

What traders do

Using the same 30-pip stop regardless of ATR reading

The consequence

When ATR is 25 pips, a 30-pip stop is only 1.2× ATR — statistically, price will hit your stop on 35% of trades just from noise. Your strategy never gets a chance to work.

What to do instead

Use ATR to set your stop. A 2× ATR stop gives price room to breathe while still limiting risk.

#2: Ignoring ATR Regime Changes

What traders do

Using a single ATR value for days or weeks without checking if volatility has shifted

The consequence

ATR can double during economic events. If you set your stop at 1.5× ATR (say 30 pips when ATR=20), and ATR jumps to 40, your effective stop is now 0.75× ATR. You'll get stopped out by normal volatility.

What to do instead

Check current ATR daily or use a rolling ATR value when setting your stop.

#3: Setting Stop at 1× ATR

What traders do

Using the ATR value directly as your stop distance without a multiplier

The consequence

ATR measures average range. About 30-40% of daily bars will exceed their ATR. A 1× ATR stop gets hit too often. At 2× ATR, noise-based stop-outs drop significantly.

What to do instead

Use 1.5× to 3× ATR as your stop. Start with 2× and adjust based on your strategy's average winning move.

The Math Behind ATR Position Sizing

Step 1: Calculate stop distance

Stop Distance = ATR × Multiplier = 20 × 2 = 40 pips
ATR: 20Multiplier: 2Stop Distance: 40 pips

Step 2: Calculate position size

Risk Amount = Balance × Risk% Position Size = Risk Amount / (Stop Distance × Pip Value) = $200 / (40 × $10) = 0.50 lots
Balance: $10,000Risk %: 2%Position Size: 0.50 lots

Step 3: Adjust for volatility change

New ATR = 40 (high volatility) New Stop = 40 × 2 = 80 pips New Size = $200 / (80 × $10) = 0.25 lots → Same risk, wider stop, smaller size
New ATR: 40New Size: 0.25 lotsRisk: $200

Step 3: Adjust for volatility change