Consistent Hashing Ring Simulator — Interactive System Design Lab

Visualise how consistent hashing distributes keys across a ring of servers. Add or remove a node and watch the exact keys that get redistributed light up in real time — confirming that only the minimal set of keys moves. Understand why DynamoDB, Cassandra, and CDNs use this instead of modulo sharding.

Add and remove nodes to see minimal key remapping in action.

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

Read the guide

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