What P/E means

P/E — price-to-earnings — is the most quoted valuation ratio there is: how many rupees is the market charging for every rupee of a company’s annual earnings? Framed differently, it’s roughly how many years of current profit an investor is paying for at today’s price — a rough framing, since it ignores both growth and the time value of money (a rupee earned in year ten is worth less than one earned today).

The formula

P/E = Price per Share / EPS

For a company that has just issued fresh shares, this series uses post-issue EPS — profit divided by the share count after the issue. The last post showed exactly why that matters.

Worked example: Desi Bites Foods Ltd

   
IPO Price ₹640
÷ Post-issue EPS ₹16.72
P/E 38.3x

Worth seeing the gap explicitly: on pre-issue EPS (₹20.9), P/E would come out to 30.6x. That’s not an error as such — Indian IPO offer documents often quote P/E on pre-issue EPS — but it’s a materially lower number. The post-issue P/E better reflects what a listing-day buyer is actually paying, because the fresh shares are real and share the same profit from day one.

Worked example: Britannia Industries

Price is Britannia’s NSE closing price on 30 June 2025 (source: Yahoo Finance historical data), paired with the FY25 EPS from the audited consolidated results — i.e. roughly what the market was paying for Britannia’s FY25 earnings shortly after those results were digested. For illustration only, not a signal to act on.

   
Price (30 June 2025) ₹5,851
÷ EPS ₹90.45
P/E 64.7x

A P/E of 64.7x means the market was pricing Britannia at roughly 64.7 years of its FY25 earnings. Across this series, the same company has shown ROE (return on equity) above 50%, negative net debt, and a negative cash conversion cycle. Mechanically, a high multiple means the market is paying for expected quality or growth — whether 64.7x is justified isn’t assessed here, and this series deliberately doesn’t answer that question.

Common mistakes

  • Treating high P/E as automatically overvalued, or low P/E as automatically cheap. Both readings skip the actual question: is the multiple justified by the quality and durability of the earnings behind it? A “cheap” P/E on a deteriorating business can be far riskier than an “expensive” one on a genuinely strong one.
  • Mixing trailing and forward EPS without checking which is being used. This series always uses trailing (historical, already-reported) EPS — some sources quote forward (analyst-estimated) EPS instead, which produces a different P/E for the same price.
  • Comparing P/E across industries or growth profiles without context. A slow-growing utility and a fast-growing FMCG (fast-moving consumer goods) brand can both have “reasonable” P/Es that mean completely different things.
  • Ignoring earnings quality behind the E. A great P/E on paper means little if the earnings themselves aren’t backed by real cash — worth checking OCF/PAT before trusting a P/E at face value.

Takeaway: P/E measures roughly how many years of current earnings the market is charging for a share. It only means something next to the quality and growth of the earnings underneath it — never as simply “high” or “low”.