How to ask someone out after they've gone quiet for three days

Look at the last thing she actually sent. If it had a question, a story, or a hint of plans, three days is just the time it took her to get round to it. If it was a one-word reply or a sign-off, the thread was already winding down before the gap started, and you're not dealing with a delay so much as a conversation that needs a new angle.

Also check your own side. If your last message didn't give her anything to respond to, that's the more likely reason for the quiet. People answer what's easy to answer. A message with a specific thing to react to will almost always get a reply faster than a message that just keeps things warm.

A good move here does three things. It refers back to something real from the conversation so it doesn't feel like a cold open. It proposes a concrete plan, with a day or a rough window, so she doesn't have to start the planning herself. And it's light enough that saying no or saying later is easy, which paradoxically makes yes more likely.

Avoid tying the invitation to the silence. Don't reference the gap, don't ask whether she's still interested, and don't frame the message as a test. Just pick up the thread, make the suggestion, and let her decide.

Send the message in the middle of her ordinary day, not late at night when it reads as a bid for attention. If she usually answers within a few hours, a full day of silence after your message is a signal. Give it a day or two before doing anything else.

If there's still nothing after a second message spaced a few days later, stop. One follow-up that's clearly low-pressure is fine. A third message is where things tip into chasing, and that's the point where you've got your answer, even if she never says so directly. Move on and let the next conversation be the one that matters.