Frequently asked questions
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Q.What is ONNJ?↓
A.A web service that records and analyses League of Legends in-house games (custom games). Drop in a replay file and champions, KDA, gold, damage and vision are saved automatically, building rankings and stats for your group. It also handles scheduling and AI team balancing.
Q.Is it really free?↓
A.Yes — every feature, forever. We have no plans for paid tiers or locked features. Server costs are covered by donations and ads.
Q.How do I add a match?↓
A.Download the replay from your match history in the League client, then pick that .rofl file here. Check what we read from it, confirm, and you're done. A five-step walkthrough shows you where everything is.
Q.Where are replay (.rofl) files?↓
A.On Windows: Documents > League of Legends > Replays. Files are named by region and game ID, like KR-8321953519.rofl, so you can search the game ID you copied from the client. A replay only appears there once you've downloaded it.
Q.Do my replay files get uploaded?↓
A.No. The file is parsed inside your browser and only the extracted match stats are sent to our server. We never store the original .rofl file.
Q.How do I create a group and invite people?↓
A.Sign in with Google, create a group, and your dashboard is ready. Inviting takes one link — copy the invite link from Group Settings and drop it in your chat. Whoever opens it just signs in and joins automatically. No codes to pass around.
Q.Does it track ARAM too?↓
A.Yes. ARAM has no lanes, so it's scored its own way instead of by role, and it's kept separate from your Summoner's Rift records.
Q.How are OP Score and Impact calculated?↓
A.Not just kills and deaths. Combat, growth, objectives, utility and tanking are each weighted differently per role, and a small sample counts for less. Two wins in two games will never outrank twenty games of steady play. We don't publish the exact weights — people would play for the number instead of the game, and the records would stop meaning anything.
Q.What does AI Team Builder use to build teams?↓
A.Rank, preferred roles, and an internal skill rating computed from your group's own games. It respects role preferences while pulling both teams' expected win rate toward 50%. The more accurate everyone's current rank, peak rank and playable roles are, the better it gets.
Q.Is this an official Riot Games service?↓
A.No. ONNJ isn't endorsed by Riot Games and doesn't reflect the views of Riot Games or anyone officially involved in producing or managing League of Legends. League of Legends and Riot Games are trademarks of Riot Games, Inc.
For step-by-step walkthroughs, see the guides.