Even if we base our work on Google Ajax Apis which offer a language recognition api themselves, we decided to run a couple of APIs too, offering some more datas and a different structure.
By now we support Json and Xml output formats and just a parameter. Our APIs can be queried from curl,wget or similar softwares/libraries so that quite any language can read it.
Our service is free for common uses, but as we need to protect our server and resources, we decided to introduce an authentication system based upon an API key, which you can retrieve for free from our website.
Using a registered API key would allow you to perform up till 1,000 calls per hout, which is ~720,000 per month! This number is huge, and usually medium sized non-commercial websites would not feed the necessity of having more.
Anyway if you have special necessities, please feel free to contact us at people@langid.net
If you don't register your API key and want to use them freely, you can, but we'll block your calls after 100 per hour per ip.