Some days you get a definite sense that something is off on Twitter. People seem angry or worried one day, extra-happy and goofy the next – it’s the land of 10,000 mood swings.

Ever wonder if your experiences on Twitter jibe with the rest of the Twitterverse? This hedonometer provides an answer.

Pulling from Twitter’s Gardenhose feed (a random sampling of roughly 50 million (10%) of all messages posted to the service), the Hedonometer assigns tweets words a “happiness score.”

To quantify the happiness of the atoms of language, we merged the 5,000 most frequent words from a collection of four corpora: Google Books, New York Times articles, Music Lyrics, and Twitter messages, resulting in a composite set of roughly 10,000 unique words. Using Amazon’s Mechanical Turk service, we had each of these words scored on a nine point scale of happiness: (1) sad to (9) happy. You can explore the average scores of each word on our words page, or download the entire list from the publication supplement here.

What have the happiest days been on Twitter since 2008? Christmas Day wins out every year, by far. We are a greedy people:

Looking at one year in full, the “happy during the holidays” trend continues, showing upticks on Valentines Day, Mother’s Day,  Thanksgiving and such. The saddest days tend to correspond to horrible events, with the saddest day on Twitter in 2012 being December 14, the day of the elementary school shooting in Connecticut.

So if you want to see how people are feeling on a particular day (and what they’re tweeting to make this determination), check it out. Seems tweeps were a bunch of grumpbutts yesterday. Let’s hope the rest of the week goes a little better:

It will be interesting to observe the mood on Twitter today and see if your experience matches up with the data. As you hover over specific days, you’ll see graphs like the one above detailing why the day is happier/sadder than the average.

Are you seeing happiness on Twitter today? Check the site tomorrow and see if it matches up!

(Image from Shutterstock)