I watched a coworker navigate a spreadsheet once. She right-clicked to copy. Moved the mouse to the toolbar. Clicked paste. Right-clicked again. Format cells. Dialog box. Click. Click. Click. It took her 12 seconds to do what three keystrokes do in one second.

I do not say this to make fun of her. I say it because most people use maybe 5% of the shortcuts available to them, and the cumulative time loss across a year is measured in days, not hours. Here are the shortcuts that actually make a difference — not the obscure ones you will forget tomorrow.

The Big Six (Learn These First)

• Ctrl+C / Ctrl+V: Copy and paste. You probably know these. Good.
• Ctrl+Z: Undo. The most underused shortcut. Works in almost every application, including web forms and file operations.
• Ctrl+Shift+T: Reopen the last closed browser tab. I use this 20 times a day. You close a tab by accident, you panic, you remember this shortcut exists, crisis averted.
• Alt+Tab (Windows) / Cmd+Tab (Mac): Switch between open applications. Do not reach for the mouse.
• Ctrl+F: Find on page. Works in browsers, PDFs, Word, Excel, code editors. If you are scrolling with your eyes to find a word, stop.

The Life-Changers

• Windows Key + V: Clipboard history. Every thing you have copied recently, right there. I cannot believe I lived without this.
• Ctrl+Shift+V: Paste without formatting. No more pasting giant bold text from a website into your email.
• Windows Key + Shift + S: Snipping tool screenshot. Drag and capture exactly what you want.
• Ctrl+W: Close current tab. Paired with Ctrl+Shift+T (reopen), you can close and restore tabs without touching the mouse.