Here You can quickly check Alexa Rank for each website, just enter your domain name bellow and press Check Alexa Rank button.
More website related to SEO - higher Alexa ranking it have, It's because much more people using Alexa Toolbar which is used to determine Alexa ranking.
The diference in traffic can be up to 10x, keep in mind it. So, if you compare a sites, compare them in same topic. Not related to SEO website can have real traffic from 200~1000 visits dailly with Alexa ranking ~ 3.000.000
There is also the difference between countries, Alexa it's most popular in India. For an example: often real traffic from United States are higher, but alexa site showing opposite way.
For quickly boost Alexa Ranking of your blog or site, you should use knowledge, that in some countries alexa toolbar is often used, what mean that by increasing traffic from those countries you will increase alexa rank faster than by increasing traffic from other countries.
To get traffic from specific country, you can create set of sattelite sites or PBN's using expired domains list, where you can find expired sites having traffic in your topic from particular country. By redirect or link from those sites - you can simply boost traffic for your domain and as the result - increase alexa ranking.