Best way to track someone else's traffic?

[SonicReducer]

Is there a good way to find out detailed traffic stats for a site that is not yours? Something like Alexa's traffic charts, but actually accurate? I want to check out traffic patterns on a site I am about to buy advertising on, and want my own analysis of the traffics. Thanks for any tips in advance.

[WorldImpulse]

If you want to advertising you can straight away ask them for the traffic stats.

[ewan]

Our company uses Hitwise to get an idea of competitor/potential advertiser traffic and market share. The way Hitwise works is gather the data from ISPs in the country, put it in their database and produce easy to read reports. In a way, its fairly accurate. However, in Hitwise reports they never give you an exact number.

Furthermore, its not meant for small businesses as the yearly subscription fee is quite high.

The major downside is although it gives you a good insight on major websites, on smaller websites you'll get hardly anything or worse its not in their database. But that may be the way the website may be, just unknown.

It also has reports directly related to affiliate marketing, and estimates how much traffic it may give you.

[Richie_Ni]

That's a little hard ,maybe you could ask the hackers