The American and French Revolutions were similar in several ways. Both revolutions were to protest the form of government known as a monarchy (or king). In both countries, the king had complete control and the citizens had almost no voice. Both kings also had major flaws- King George III of England suffered from mental health problems, and King Louis XVI of France was young, inexperienced, and out of touch with the French people. Second, both revolutions were inspired by ideas of the Enlightenment. The Enlightenment was a change in the way people viewed individuals, society, and the role of government. Some key ideas of the Enlightenment that inspired revolution in both America and France included John Locke's idea of natural rights; Voltaire's concept of free speech; and Montesquieu's description of separation of governmental powers. Finally, it should be noted that many Frenchmen who helped America in their revolution were inspired to change France when they returned.
However, there are key differences between these two revolutions. First, Americans were fighting against a king that was limited in his power somewhat and thousands of miles away. The French were fighting a king within their own country. Second, the absolute monarchy in France was a key part of the social order that had been in existence for centuries. It was much more difficult in France to break down that entrenched system, known as the estates. The educated and wealthy in France had the most privileges, and wanted these protected; however, in America it was the educated and wealthy who led and financed the revolution! Also, France was fighting not only a revolution within its borders, but a war against neighboring European nations who wanted to prevent the rebellion from spreading.
One final key difference is how these revolutions concluded: America gained independence and became its own nation, while France was conquered by Napoleon Bonaparte, who would then go on to establish an empire across much of Europe.