# How do I retrieve the "COMP earned" value?

## With a Smart Contract or JSON RPC

Get the value of COMP earned for an address that uses the Compound protocol. This can be done using the Lens contract with JSON RPC or another Smart Contract. If you do an `eth_call` with JSON RPC, it is free (no gas costs).

1. Use the `getCompBalanceMetadataExt` method in the Lens contract 
https://etherscan.io/address/0xd513d22422a3062Bd342Ae374b4b9c20E0a9a074#code
2. Lens address is posted here https://github.com/compound-finance/compound-protocol/blob/master/networks/mainnet.json#L11
3. Here is the definition https://github.com/compound-finance/compound-protocol/blob/master/contracts/Lens/CompoundLens.sol#L278
4. pass: COMP contract address, Comptroller contract address, and the address you want to know the amount of COMP earned

## With API

There is an API endpoint hosted by Compound Labs. This data is slightly behind the blockchain information with respect to time. Use URL parameters to provide the `address` that you wish to retrieve the COMP accrued value.

```
HTTP GET https://api.compound.finance/api/v2/governance/comp/account?address=0x123123123123abcabcabcabcabcab
```

Use the returned `comp_allocated` value in the JSON object response.

## Tools

Alternatively there is a cool tool from KZen networks that does the same thing.
https://github.com/KZen-networks/compound-playground#comp

KZen also created the COMP checker page: https://kzen-networks.github.io/comp-checker/