Settle a rule — or start a sport.
Not sure what to play?
Pick a vibe or category. Roll. Re-roll until something clicks.
Rolling for: 🎲 Random
Free Game Tools
No signup. Use them mid-game on any device.
Settle It Instantly
Real rule disputes — answered with official sources.
“What is team composition in Netball?”
Each team fields seven players on court at any time, drawn from a match squad of up to twelve.
“What is 10 m air rifle/pistol range in Shooting?”
Distance: 10 m (32.8 ft) from firing line to target face; Indoor facility: Temperature-controlled, enclosed, with con...
Shooting · #playing-areaRead full rule →“What is the safety considerations in Basketball (FIBA)?”
FIBA has implemented comprehensive concussion management procedures for all Level 1 and Level 2 competitions: Recogni...
Basketball (FIBA) · #safety-considerationsRead full rule →“What is the safety considerations in Lacrosse (NCAA Men)?”
NCAA men's lacrosse mandates NOCSAE-approved helmets and mouthpieces, properly fitted shoulder pads, arm pads, gloves...
Hot Rules Right Now
Most-viewed official rulebooks this week
Featured Sports
See all →
Summer Sports
Warm-weather and outdoor sports
Did You Know?
10-Point Must System
Same rule. Different sports. Different answers.
IBF
All IBF championship bouts are scored using the 10-point must scoring system. Under this system, the winner of each round receives 10 points, and the loser receives 9 points or fewer.
PowerSlap
Matches are scored on the 10-Point Must System. Open scoring may be used at the Promoter's election, in consultation with the Executive Director and/or Commission.
Gaining Traction
Community sports picking up momentum right now
Recently Updated Rules
Official rulebooks with fresh changes
ISU
25 rules updated · 13d ago
Latest: 6.3 Mass Start Scoring
FIS
28 rules updated · 13d ago
Latest: 7.1 Snowboard Cross Contact Rules
FIS
22 rules updated · 13d ago
Latest: 5.4 Wind and Gate Compensation System
IBSF
34 rules updated · 13d ago
Latest: 2.3 Suit and Shoes
ISU
29 rules updated · 13d ago
Latest: 8.3 Medical Protocols
FIS
31 rules updated · 13d ago
Latest: 6.1 Jumping Score Calculation
No More Arguing
Search the Rule
“Is a double dribble legal?” “Can you bounce in beer pong?”
Get the Verdict
Cited rule number and source. No opinions — just the answer.
Send the Proof
Share a direct link. One tap — argument over.
No more guessing. No more debates.
Every official sport started somewhere
How a Sport Becomes Official
Open Source Sports gives new sports a visible path forward.
Most sports never reach this stage. Yours can.
This is the path every custom sport follows on Open Source Sports.
What are you here for?
Two tracks, one platform. Pick your path.
Official Sports
Trusted rules from real governing bodies.
- ✓ Verified rulebooks, cited with rule numbers
- ✓ League comparisons and seasonal updates
- ✓ Instant verdicts for common disputes
NFL, FIFA, NBA, UFC, and 151 more
Settle a RuleCustom Sports
Turn your idea into a recognized sport.
- ✓ Create your own sport from scratch
- ✓ Community voting and rule proposals
- ✓ Path to endorsement and official status
Beer pong, backyard games, and your next idea
Create a SportSport of the Day
Valve
Dota 2
Dota 2 is a multiplayer online battle arena (MOBA) game developed by Valve Corporation. Two teams of five players each select heroes from a pool of over 120 and compete to destroy the opposing team's Ancient, a core structure in their base.
Explore by Category
Who Decides the Rules
Sourced from 92 governing bodies worldwide.
Help Keep the Rulebook Open
OpenSourceSports stays useful when people improve the rules, suggest missing sports, and support the tools that keep play moving.