Historical Reindex Progress Tracker

WHAT IT DOES

The Historical Reindex Progress Tracker is an analytics tool that monitors and visualizes the progress of an indexer's historical reindexing operation. It tracks the indexer's latest block against a user-defined start block and an optional end block (or the current reference block), calculating how much of the historical range has been indexed. The tool displays progress as both a percentage and the number of blocks remaining, with an estimated completion time based on 12-second block intervals. This helps developers and infrastructure operators track the status of large historical indexing operations, estimate completion times, and identify potential stalls or slowdowns.

HOW TO USE

Enter the RPC URL of the indexer you want to monitor. Specify the start block of the historical range you're indexing (e.g., the deployment block of a contract). Optionally set an end block—if left empty, the tool will use the current reference block from your connected wallet. Configure the update interval (default 10 seconds) and click "start tracking." The tool will continuously poll the indexer, compare its latest block against the reference block, and display progress updates. Results include progress percentage, blocks remaining, estimated time to completion, and a historical progress chart showing the last 10 snapshots.

TECHNICAL MECHANISM

The tracker creates an ethers JsonRpcProvider instance for the user-provided indexer URL and issues eth_blockNumber requests at the configured interval. It fetches the reference block number from the wallet's connected provider using getBlock('latest'), providing a trusted baseline for the current chain head. The total range is calculated as (endBlock - startBlock), where endBlock defaults to the reference block if not specified. The indexed range is calculated as (indexerLatest - startBlock), capped to not exceed the total range. Progress percentage is (indexedRange / totalRange) × 100. The tool stores timestamped snapshots of block number and progress percentage in memory, displaying the most recent 10 entries as a simple history table. Estimated completion time is calculated as (blocksRemaining × 12 seconds), providing a rough ETA. The monitoring loop continues until stopped, with automatic error handling that preserves the last valid state.

WHAT IT CANNOT SEE

The tool cannot determine the exact progress of third-party subgraphs or specialized indexers without their own APIs. It cannot detect reorgs that may affect historical indexing accuracy, as it only checks block numbers, not data integrity. The tool cannot measure indexer coverage for specific contract events or logs beyond block range. It cannot predict completion time for large historical ranges without additional data about indexer performance. The tool cannot account for indexer-specific optimizations or caching strategies that may affect reported progress. It cannot verify whether indexed data is correct or complete—only that block numbers have been processed. The tool cannot monitor all available indexers simultaneously or compare their performance.

PLEASE NOTE

This tool is designed for Ethereum Virtual Machine (EVM) compatible chains only. The estimated completion time assumes a constant 12-second block time, which varies by chain and network conditions—users should adjust expectations for different networks. The tool provides estimates only and should not be used as the sole basis for critical infrastructure decisions. The reference block is fetched from your wallet provider, which may itself have a slight lag. The tool stores history only in memory; refreshing the page will clear all history. Different indexers may report different latest block numbers depending on their sync strategy and infrastructure.