Database Sharding Simulator — Interactive System Design Lab
Add data and watch it distribute across database shards using range-based and hash-based partitioning. See exactly which records land on which shard, observe hot-spot behaviour with skewed keys, and understand why rebalancing is the operational challenge that makes sharding difficult in practice.
Write records and watch them land on shards — then see why rebalancing is the hard part.
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
- database sharding
- horizontal partitioning
- hash sharding
- range sharding
- database scaling
Read the guide
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