1. OBS Studio (Best for Professional Control)
Open-source, free forever, and capable of multi-source recording, hardware encoding (NVENC/AMD), and 4K 60fps output.
2. Windows 11 Snipping Tool (Best Built-in Tool)
Press Win + Shift + S, switch to the video camera icon, and drag your recording region. Zero setup required.
3. Xbox Game Bar
Press Win + G or Win + Alt + R for instant single-window application recording.