Uno
Card Games · 13 specs
Direct Answer
Uno is a 108-card shedding game governed by official Mattel standards. Official rules strictly prohibit stacking draw cards (+2 on +2 or +4 on +4); affected players must draw and forfeit their turn. Players may legally finish on action cards, and a Wild Draw 4 may only be played when holding no cards of the active color.
Source: Mattel Official Uno Rules (Standard Edition) · Last reviewed Aug 28, 2026
Specs
| Governing Publisher | Mattel |
| Total Deck Size | 108 cards |
| Starting Hand Size | 7 cards |
| Target Winning Score | 500 points |
| Card Stacking (+2 / +4) | Prohibited (Illegal) |
| Ending on Action Card | Permitted (Legal) |
| Wild Draw 4 Legality | Legal only if holding no active color |
| False Challenge Penalty | 6 cards |
| Guilty Challenge Penalty | 4 cards |
| Uncalled Uno Penalty | 2 cards |
| Numbered Cards Value (0–9) | Face Value (0–9) points |
| Action Cards Value (Skip/Rev/+2) | 20 points |
| Wild Cards Value (Wild/Wild +4) | 50 points |
Official 108-Card Deck Breakdown
A standard Uno deck contains exactly 108 cards across four suits (Red, Yellow, Green, Blue):
- Numbered Cards (76 Total): 19 cards per color. Each color has one '0' card and two each of numbers 1 through 9.
- Action Cards (24 Total): Two Draw Two (+2), two Reverse, and two Skip cards per color.
- Wild Cards (8 Total): Four Wild cards (choose color) and four Wild Draw Four (+4) cards.
The Stacking Myth vs. Official Rule
A widespread house rule allows players to stack +2 cards on top of +2 cards (or +4 on +4) to pass accumulated draw penalties to the next player. Mattel's official rules explicitly state that stacking is illegal. When a Draw Two or Wild Draw Four is played, the immediate next player must draw the indicated number of cards and forfeit their entire turn. No card may be played to redirect the penalty.
The Wild Draw 4 Challenge Rule
A player may only play a Wild Draw Four if they do not hold any card matching the currently active color on the discard pile. (Holding matching numbers of different colors or other action cards is permitted).
The player facing the +4 may challenge before drawing:
- If the +4 player is Guilty: The player reveals their hand. If they hold a card of the active color, they must draw the 4 cards themselves.
- If the +4 player is Innocent: The challenger must draw 6 cards total (the original 4 + 2 penalty cards) and forfeits their turn.
Calling Uno & Winning on Action Cards
- Calling Uno: A player must announce 'Uno' before their second-to-last card touches the discard pile. If caught by an opponent before the next player draws or plays, they must draw 2 penalty cards.
- Action Card Finishes: A player can legally win the game by playing an action card as their final card. If the winning card is a +2 or +4, the next player must still draw those cards, and their point values are added to the winner's score.
Official 500-Point Scoring System
When a player empties their hand, they receive points for all cards remaining in all opponents' hands:
- Numbers 0–9: Face value (0 to 9 points)
- Skip, Reverse, Draw Two: 20 points each
- Wild, Wild Draw Four: 50 points each
The first player to accumulate 500 points across rounds wins the overall match.