Prepared coffee definitely has more caffeine than tea. Here's one example source showing the difference. It seems that although raw tea leaves contain a higher caffeine content than raw coffee beans, coffee is prepared in a way that extracts more caffeine into the drink.

The numbers on that link show that:

"An average cup (220 ml) of black tea packs 50 mg of caffeine but can contain more" (if steeped for longer)

"An average 8-ounce (237-ml) cup of coffee contains 90 to 200 mg of caffeine."

There's a lot more information on that link, but it seems that prepared coffee generally contains somewhere between 2-4x as much caffeine as the same amount of prepared tea.