I used to round everything to .25 hours because that's what my invoicing tool required. Thought I was being professional. Turns out I was leaving like $400/month on the table because I'd consistently round down instead of logging the actual 8 or 12 minutes.

Started tracking exact time and holy shit, those little 10-minute client calls and quick revisions actually add up. I'm not saying nickel-and-dime your clients, but if you worked it, log it. I built a timer that just floats on my screen so I never forget to start it, and my invoices went up 15% without changing my rates at all.

Anyone else been undercharging themselves like this or am I just bad at math?