Polygon zkEVM batches users' transactions and submits them to Ethereum, paying a share of the transaction fees to Ethereum validators (supply-side fees).

Polygon zkEVM is an L2 smart contract platform for decentralized applications on Ethereum. Polygon zkEVM was founded by the Polygon team and launched in 2023.

Polygon team owns and governs the protocol. Polygon’s investors include Coinbase Ventures, ZBS Capital, MiH Ventures, etc.

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Polygon zkEVM

# Polygon zkEVM Bridge Deposits Methodology

## 1. Overview

Bridge deposits for Polygon zkEVM measures the cumulative net value of assets bridged to the network via the AgglayerBridge contract on Ethereum. The metric is computed as deposits minus claims (withdrawals), representing the total capital currently locked in the canonical bridge. This serves as an indicator of capital inflows and user adoption of the Layer 2 network.

## 2. Data sources

- **AgglayerBridge BridgeEvent**: Decoded deposit events on Ethereum filtered to `destinationNetwork=1` (Polygon zkEVM)
- **AgglayerBridge ClaimEvent v1**: Decoded withdrawal claims from the original PolygonZkEVMBridge contract (2023-03 to 2024-02)
- **AgglayerBridge ClaimEvent v2**: Decoded withdrawal claims from the upgraded AgglayerBridge contract (2024-02 onwards), filtered by `globalIndex` to isolate Polygon zkEVM claims
- **End-of-day price feeds**: Daily token price data for USD conversion
- **Token metadata**: Token contract information including decimal places for proper amount normalization

## 3. Step-by-step calculation

### Component A: Deposit extraction
- **Purpose**: Capture all assets deposited to Polygon zkEVM via the shared AgglayerBridge on Ethereum
- **Logic**: BridgeEvent events are extracted from the AgglayerBridge contract on Ethereum, filtered to `destinationNetwork=1` (Polygon zkEVM) and `leafType=0` (asset transfers). The zero address is mapped to WETH.
- **Key fields**: `block_timestamp`, `token_address`, `amount`

### Component B: Claim extraction (withdrawals)
- **Purpose**: Capture all assets withdrawn from Polygon zkEVM back to Ethereum
- **Logic**: ClaimEvent events are extracted from two contract versions due to a proxy upgrade in February 2024. The v1 contract (PolygonZkEVMBridge) emitted ClaimEvents from 2023-03 to 2024-02 — all events on Ethereum are zkEVM withdrawals since it was the only rollup at the time. The v2 contract (AgglayerBridge) emits ClaimEvents from 2024-02 onwards — filtered by `(globalIndex >> 32) = 0` to isolate Polygon zkEVM (rollupIndex=0) from other Agglayer chains. Claims are subtracted from deposits to compute net flows.
- **Key fields**: `block_timestamp`, `token_address`, `amount` (negated)

### Final aggregation
- **Net flows**: Deposits and claims are unioned, with claims negated. Amounts are normalized by token decimals and aggregated daily per token.
- **Cumulative sum**: A running sum over time per token produces the cumulative net balance for each asset.
- **Fill forward**: Days with no activity carry the previous day's cumulative balance forward.
- **Currency conversion**: Cumulative balances are converted to USD using end-of-day price feeds.
- **Final output**: USD values are summed across all tokens to produce the daily aggregate bridge deposits metric.

*This methodology was automatically generated by Token Terminal's methodology analyzer.*

Value of assets held in a project's bridge contracts.

Polygon zkEVM

Bridge deposits

Bridge deposits

Competitive landscape

Chain breakdown