Stop 06 · Paid Advertising (PPC)Topics · 1/12

How PPC Auctions Work

In short

Every time someone searches, an auction finishes in a blink. The surprise: the richest bidder often loses to a smaller brand with a more useful ad.

Ad platforms run a real-time auction for each ad slot, ranking bidders by a combination of bid amount and ad quality — understanding this explains why the highest bidder doesn't always win.

The blob landlord holds a house key and compares two folders from hopeful tenants.

Think of it like this

Choosing a tenant for a flat

A landlord in Pune gets two offers. One tenant offers more rent but has bad references. The other offers a little less, pays on time and keeps the place clean. Most landlords pick the second. Ad platforms think the same way.

Watch it happen

Three ads compete for one search (simplified)

A: ₹40 x QS 4

B: ₹25 x QS 8

C: ₹30 x QS 5

1/5Three advertisers bid on 'coaching for CAT'. Each bid is paired with a quality score from 1 to 10.

The big ideas

What you need to know

An auction per search

The auction runs fresh for every single search or page view, so your position changes all day.

Quality counts

Platforms reward ads people are likely to click and find useful, because happy users keep coming back.

You rarely pay your max

You set a maximum bid. You usually pay closer to what it takes to beat the ad below you.

Pay per click

In PPC you pay only when someone clicks, not when the ad is merely shown.

See it in code

Walk through the code

excel

1Ad Rank      = Max CPC x Quality Score2B: 25 x 8    = 200   (1st)3A: 40 x 4    = 160   (2nd)4 5Price B pays = Ad Rank below / B's QS + ₹0.016             = 160 / 8 + 0.017             = ₹20.01 per click

1/3Your position depends on bid and quality together, not bid alone.

The classic textbook model of a search auction. Real Google auctions use more signals, but this shows why quality lowers your cost.

Save yourself the pain

Common mistakes

Oops

Raising bids every time your ad slips down.

Do this instead

First fix relevance: tighter keywords, better ad text, a matching landing page. That often lifts rank more cheaply.

Oops

Thinking you pay your maximum bid on every click.

Do this instead

Max bid is a ceiling. The actual cost per click is usually lower and depends on competitors.

Your mission

Run a paper auction

~15 min

Quick check

Advertiser X bids ₹50 with a poor ad. Advertiser Y bids ₹30 with a very relevant ad. Who can win the top slot?

Go deeper

1Learn the concept of Ad Rank (bid × quality/relevance) at a conceptual level.
2Understand why a highly relevant, well-targeted ad can beat a higher bid with poor relevance.
3Practice explaining why quality score matters as much as budget in paid search.