Roll 1d20

1d20 rolls from 1 to 20 with an average of 10.5. It rolled once when the page loaded; press Roll for another.

Choose your roll

Use a quick die, type notation such as 2d6+3, or configure the dice and modifier separately.

Roll 1d20

Quick rolls

Dice ready

Your next roll lands here.

The total, individual dice, dropped values, and a running history of up to 20 rolls will stay together.

This page rolls a single 20-sided die (1d20) the moment it loads and again every time you press Roll. Results run from 1 to 20 with an average of 10.5. In D&D 5e the d20 decides attack rolls, saving throws, ability checks, and initiative. A natural 20 on an attack is a critical hit.

Questions

What is the average roll of 1d20?
The average of a single d20 is 10.5: every face from 1 to 20 is equally likely, so the expected value is (1 + 20) divided by 2.
How do I add a modifier to 1d20?
Type the full expression in the dice notation field, for example 1d20+3 or 1d20-1, and press Roll notation. The total shown includes the modifier.
Is this dice roller free?
Yes. Every tool on Tools and Taverns is free, with no account, signup, or roll limit. The roll runs in your browser and nothing is sent to a server.
Can I see my previous rolls?
Yes. The roller keeps your last 20 rolls on screen with the individual dice for each, so a contested result is still there when someone asks what you got.