On Dictation.io you can simply click "start dictation" then start having your voice transcribed into a text document. No registration is required in order to use Dictation.io. More than two dozen languages are support on Dictation.io. The video embedded below provides a demonstration of Dictation.io.
In Google Chrome you can use the Dictanote Speech Recognizer app available for free through the Chrome Web Store. To use the Dictanote Speech Recognizer just install it from the Chrome Web Store, launch it, then click the microphone to start taking and recording your voice. The Speech Recognizer will type out your text when you finish recording. You can then copy and paste your text to the paragraph box below the Speech Recognizer or to a document you have open in Google Docs.