When Google estimates traffic on PPC what is the actual figure based?

[Macbeth]

Yes, when I sayI'll bid £10 per click for a set of keywords it says that I'll get say 500 clicks.

But what is this based on?

Does it mean that i will have 500 searchers exposed to the advert each day

or is this based on say 1000 surfers at a CTR of 50% for example?

[mikeyrhodes]

test & learn ;)

[annej]

I'm finding the estimates aren't very accurate in a niche topic.

[marek]

I suppose Google's traffic estimates are based on average number of impressions and average CTR, however they are very inaccurate even for quite high-volume keywords.

[mikeyrhodes]

It's based on a while bunch of things.
You'll notice as you drop your bid, the estimated number of clicks will drop too.
That's coz G knows that in position #1 you'll get heaps more clicks than you will at #8 (or #15 etc)

Also if you haven't run your ad yet, yes G will estimate a CTR for you until you have some real results. Best I can tell this varies depending on the niche, often seems to be around 1% though.
Again, I think it adjusts this based on your bid & therefore position... no idea how!

Best bet - if you're new to it. Aim for position 5. Set your bid & keep a very close eye on it for the first few days.
You'll learn fast & improve from there.
Keep your budget as high as you can (much higher than G suggests if you can)

Good luck :)

Mikey

[Macbeth]

Thankyou all, so just to clarify and perhaps round up. Google predicts your clicks by assuming a certain CTR depending on your overall average ranking position (set by the bidding amount placed).

[eWhisper]

Thankyou all, so just to clarify and perhaps round up. Google predicts your clicks by assuming a certain CTR depending on your overall average ranking position (set by the bidding amount placed).

Correct.

Google looks at the keyword & bid price you entered, predicts a CTR, and then gives you an estimate.

If you are using geo-targeting, these estimates often don't take that into account (i.e. often the prediction for a state is the same (or sometimes higher) than for the entire U.S.)

aside:
On the recent advertiser survey about what's the best way Google can help you sell AdWords better: My #1 answer - a semi-accurate projection system.