Unix Timestamp / Block Estimator

Estimate which blockchain block number corresponds to a given Unix timestamp, or convert a block number back to an approximate timestamp. Supports Bitcoin, Ethereum, Solana, Base, and Arbitrum.

How It Works

Each blockchain produces blocks at a roughly predictable rate. By knowing the genesis timestamp (when block 0 was mined) and the average block time, we can estimate the relationship between Unix timestamps and block numbers.

Estimated Block = (Timestamp − Genesis Timestamp) ÷ Average Block Time

Estimated Timestamp = Genesis Timestamp + (Block Number × Average Block Time)

Chain Parameters

Accuracy Considerations

• Bitcoin — Block times vary significantly (1 min to 60+ min) depending on difficulty and hash rate. The 10-minute average holds well over long periods but individual blocks can be far off.
• Ethereum (PoW) — Pre-Merge block times averaged ~13.3s but varied with network congestion and difficulty bombs.
• Ethereum (PoS) — Post-Merge blocks are produced every 12 seconds with high regularity, making estimates more accurate. Occasionally slots are missed, adding minor variance.
• Solana — Slot times average ~400ms but vary with network congestion and validator performance. Slots can also be skipped, adding gaps in the sequence.
• Base — As an Optimism-based L2, blocks are produced every 2 seconds by the sequencer. Sequencer downtime can cause gaps.
• Arbitrum — Blocks are produced on-demand by the sequencer at ~0.26s average, but timing is highly variable and depends on transaction activity.
• General — Estimates are more accurate for dates closer to the present. For historical dates, checking a block explorer is recommended for exact results.