Consistent Hashing Ring Simulator — Interactive System Design Lab
Visualise how consistent hashing distributes keys across a ring of servers — and why production systems never place a server at just one point on it. Add or remove a node and watch the exact keys that move. Then raise the virtual nodes per server and watch an uneven ring flatten, and a dead node’s keys go from dumped on one neighbour to spread across every survivor. This is how DynamoDB, Cassandra, and CDNs actually run it.
Add virtual nodes per server and watch key distribution flatten in real time.
This free interactive simulation runs directly in your browser — no account needed. Adjust the parameters and watch how the system responds in real time.
Concepts covered
- consistent hashing
- hash ring
- virtual nodes
- DynamoDB
- Cassandra
- key distribution
- key redistribution
- modulo sharding
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