Configuration

Chainlink VRF allows you to integrate provably fair and verifiably random data in your smart contract.

For implementation details, read Introduction to Chainlink VRF.

Coordinator Parameters

These parameters are configured in the coordinator contract. You can view these values by running getConfig on the coordinator or by viewing the coordinator contracts in a blockchain explorer.

  • uint16 minimumRequestConfirmations: The minimum number of confirmation blocks on VRF requests before oracles respond
  • uint32 maxGasLimit: The maximum gas limit supported for a fulfillRandomWords callback.
  • uint32 stalenessSeconds: How long the coordinator waits until we consider the ETH/LINK price used for converting gas costs to LINK is stale and use fallbackWeiPerUnitLink
  • uint32 gasAfterPaymentCalculation: How much gas is used outside of the payment calculation. This covers the additional operations required to decrement the subscription balance and increment the balance for the oracle that handled the request.

Fee Parameters

Fee parameters are configured in the coordinator contract and specify the premium you pay per request in addition to the gas cost for the transaction. You can view them by running getFeeConfig on the coordinator. The uint32 fulfillmentFlatFeeLinkPPMTier1 parameter defines the fees per request specified in millionths of LINK. The details for calculating the total transaction cost can be found here.

Configurations

Ethereum Mainnet

Item Value
LINK Token 0x514910771AF9Ca656af840dff83E8264EcF986CA
VRF Coordinator 0x271682DEB8C4E0901D1a1550aD2e64D568E69909
200 gwei Key Hash 0x8af398995b04c28e9951adb9721ef74c74f93e6a478f39e7e0777be13527e7ef
500 gwei Key Hash 0xff8dedfbfa60af186cf3c830acbc32c05aae823045ae5ea7da1e45fbfaba4f92
1000 gwei Key Hash 0x9fe0eebf5e446e3c998ec9bb19951541aee00bb90ea201ae456421a2ded86805
Premium 0.25 LINK
Max Gas Limit 2,500,000
Minimum Confirmations 3
Maximum Confirmations 200
Maximum Random Values 500

Goerli testnet

Item Value
LINK Token 0x326C977E6efc84E512bB9C30f76E30c160eD06FB
VRF Coordinator 0x2Ca8E0C643bDe4C2E08ab1fA0da3401AdAD7734D
150 gwei Key Hash 0x79d3d8832d904592c0bf9818b621522c988bb8b0c05cdc3b15aea1b6e8db0c15
Premium 0.25 LINK
Max Gas Limit 2,500,000
Minimum Confirmations 3
Maximum Confirmations 200
Maximum Random Values 500

BNB Chain

Item Value
LINK Token 0x404460C6A5EdE2D891e8297795264fDe62ADBB75
VRF Coordinator 0xc587d9053cd1118f25F645F9E08BB98c9712A4EE
200 gwei Key Hash 0x114f3da0a805b6a67d6e9cd2ec746f7028f1b7376365af575cfea3550dd1aa04
500 gwei Key Hash 0xba6e730de88d94a5510ae6613898bfb0c3de5d16e609c5b7da808747125506f7
1000 gwei Key Hash 0x17cd473250a9a479dc7f234c64332ed4bc8af9e8ded7556aa6e66d83da49f470
Premium 0.005 LINK
Max Gas Limit 2,500,000
Minimum Confirmations 3
Maximum Confirmations 200
Maximum Random Values 500

BNB Chain testnet

Item Value
LINK Token 0x84b9B910527Ad5C03A9Ca831909E21e236EA7b06
VRF Coordinator 0x6A2AAd07396B36Fe02a22b33cf443582f682c82f
50 gwei Key Hash 0xd4bb89654db74673a187bd804519e65e3f71a52bc55f11da7601a13dcf505314
Premium 0.005 LINK
Max Gas Limit 2,500,000
Minimum Confirmations 3
Maximum Confirmations 200
Maximum Random Values 500

Polygon (Matic) mainnet

Item Value
LINK Token 0xb0897686c545045aFc77CF20eC7A532E3120E0F1
VRF Coordinator 0xAE975071Be8F8eE67addBC1A82488F1C24858067
200 gwei Key Hash 0x6e099d640cde6de9d40ac749b4b594126b0169747122711109c9985d47751f93
500 gwei Key Hash 0xcc294a196eeeb44da2888d17c0625cc88d70d9760a69d58d853ba6581a9ab0cd
1000 gwei Key Hash 0xd729dc84e21ae57ffb6be0053bf2b0668aa2aaf300a2a7b2ddf7dc0bb6e875a8
Premium 0.0005 LINK
Max Gas Limit 2,500,000
Minimum Confirmations 3
Maximum Confirmations 200
Maximum Random Values 500

Polygon (Matic) Mumbai testnet

Item Value
LINK Token 0x326C977E6efc84E512bB9C30f76E30c160eD06FB
VRF Coordinator 0x7a1BaC17Ccc5b313516C5E16fb24f7659aA5ebed
500 gwei Key Hash 0x4b09e658ed251bcafeebbc69400383d49f344ace09b9576fe248bb02c003fe9f
Premium 0.0005 LINK
Max Gas Limit 2,500,000
Minimum Confirmations 3
Maximum Confirmations 200
Maximum Random Values 500

Avalanche mainnet

Item Value
LINK Token 0x5947BB275c521040051D82396192181b413227A3
VRF Coordinator 0xd5D517aBE5cF79B7e95eC98dB0f0277788aFF634
200 gwei Key Hash 0x83250c5584ffa93feb6ee082981c5ebe484c865196750b39835ad4f13780435d
500 gwei Key Hash 0x89630569c9567e43c4fe7b1633258df9f2531b62f2352fa721cf3162ee4ecb46
1000 gwei Key Hash 0x06eb0e2ea7cca202fc7c8258397a36f33d88568d2522b37aaa3b14ff6ee1b696
Premium 0.005 LINK
Max Gas Limit 2,500,000
Minimum Confirmations 1
Maximum Confirmations 200
Maximum Random Values 500

Avalanche Fuji testnet

Item Value
LINK Token 0x0b9d5D9136855f6FEc3c0993feE6E9CE8a297846
VRF Coordinator 0x2eD832Ba664535e5886b75D64C46EB9a228C2610
300 gwei Key Hash 0x354d2f95da55398f44b7cff77da56283d9c6c829a4bdf1bbcaf2ad6a4d081f61
Premium 0.005 LINK
Max Gas Limit 2,500,000
Minimum Confirmations 1
Maximum Confirmations 200
Maximum Random Values 500

Fantom mainnet

Item Value
LINK Token 0x6F43FF82CCA38001B6699a8AC47A2d0E66939407
VRF Coordinator 0xd5D517aBE5cF79B7e95eC98dB0f0277788aFF634
4000 gwei Key Hash 0xb4797e686f9a1548b9a2e8c68988d74788e0c4af5899020fb0c47784af76ddfa
10000 gwei Key Hash 0x5881eea62f9876043df723cf89f0c2bb6f950da25e9dfe66995c24f919c8f8ab
20000 gwei Key Hash 0x64ae04e5dba58bc08ba2d53eb33fe95bf71f5002789692fe78fb3778f16121c9
Premium 0.0005 LINK
Max Gas Limit 2,500,000
Minimum Confirmations 1
Maximum Confirmations 200
Maximum Random Values 500

Fantom testnet

Item Value
LINK Token 0xfaFedb041c0DD4fA2Dc0d87a6B0979Ee6FA7af5F
VRF Coordinator 0xbd13f08b8352A3635218ab9418E340c60d6Eb418
3000 gwei Key Hash 0x121a143066e0f2f08b620784af77cccb35c6242460b4a8ee251b4b416abaebd4
Premium 0.0005 LINK
Max Gas Limit 2,500,000
Minimum Confirmations 1
Maximum Confirmations 200
Maximum Random Values 500

Klaytn Baobab testnet

Item Value
LINK Token 0x04c5046A1f4E3fFf094c26dFCAA75eF293932f18
VRF Coordinator 0x771143FcB645128b07E41D79D82BE707ad8bDa1C
750 gwei Key Hash 0x9be50e2346ee6abe000e6d3a34245e1d232c669703efc44660a413854427027c
Premium 0.005 LINK
Max Gas Limit 2,500,000
Minimum Confirmations 1
Maximum Confirmations 200
Maximum Random Values 500

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