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PEG Ratio

PEG = P/E ÷ Earnings Growth Rate (%)

This number asks whether a stock's price looks fair once you factor in how fast profits are growing. P/E alone ignores growth; PEG folds it in.

01 Feel it first

Price tag that includes growth

P/E stays locked at 40×. Tap a growth preset card — slow, steady, or fast — and watch PEG = 40 ÷ growth. Below 1.0 reads cheap; above reads pricey.

P/E locked at 40×
15%Steady
PEG ratio
2.67
40 ÷ 15 = 2.67
Pricey for growth

02 Break the intuition

The 40× stock can be cheaper than the 12× stock

A high P/E can still be the better deal when growth is real. Guess which is cheaper after growth, then peel the cards.

FAST GROWER
40×
P/E · 40% growth
PEG40 ÷ 40
1.0
Cheaper
SLOW GROWER
12×
P/E · 4% growth
PEG12 ÷ 4
3.0
3× richer
The 40× stock growing 40% has PEG 1.0. The 12× stock growing 4% has PEG 3.0. Same math: you pay three times as much per unit of growth for the stock that looked "cheap" on P/E alone.

03 Dial it in

P/E and growth make PEG

Drag P/E and growth. Watch PEG move across cheap, fair, and pricey bands.

40×
60×
40%
0%50%
COMPANY A
40× · 40% growth
PEG 1.0
COMPANY B
12× · 4% growth
PEG 3.0
PEG
1.00
Fair (~1–2)
0124+

PEG = 40 ÷ 40 = 1.00. A 40× stock growing 40% lands near 1.0; a 12× stock growing 4% lands near 3.0. Growth can flip which multiple is the deal.

04 Watch the path

Growth flips which stock wins

Pick Company A or Company B. Press Play and watch earnings compound for six years.

Pick a path
Press play
$140

Earnings index starting at 100

Pick a path, then press Play to watch the years fill in.

05 Two flavors

Past growth vs expected growth

Same formula, different growth number. One looks at history. The other looks at forecasts.

Uses pastearnings growth — often the last 3–5 years. Those numbers are real, but yesterday's growth may not repeat. A company that grew 25% before can slow down; PEG then looks cheaper than it should.

06 The bands

How people usually read PEG

Rough bands, not rules. Always check the industry and whether the growth number is believable.

< 1.0 Cheap
<1
1–2 Fair
1–2
> 2 Rich
>2

Sample reading bands. Live numbers available on Amsflow.

07 Check yourself

Five quick checks

Question 1 of 5
Quick checkP/E is 30 and expected growth is 15%. PEG is:
2.0 is right. PEG = P/E ÷ growth = 30 ÷ 15 = 2.0.

08 Where it breaks

When PEG misleads you

Profits are shrinking

If earnings are falling, growth is negative and PEG breaks. The formula needs growth you can divide by.

Reported growth can be fake

EPS growth can be juiced by buybacks (company buys its own shares), one-time gains, or accounting changes. PEG inherits that fiction.

One rebound year

A single bounce after a bad year inflates growth and makes PEG look cheap. Smooth the base over a few years.

Industries have different norms

A PEG of 1.5 can look rich for a utility and normal for software. Compare within similar companies.

See PEG on a real stock.

Pull up any ticker with live P/E, growth context, and peer multiples — then screen the market for growth-adjusted value.