How much is 1 unit in USDT?

I'm curious, could you please clarify for me the exact value of 1 unit in USDT? I understand that it's a stablecoin pegged to the US dollar, but I'd like to ensure I have the most up-to-date information on its exact exchange rate. Is it indeed equivalent to 1 USD, or could there be slight fluctuations that I should be aware of? It's important for me to make informed decisions in my cryptocurrency investments, so any clarification you can provide would be greatly appreciated.