---
title: "Verify contract via similarity search"
method: POST
path: "/v2/verify/similarity/{chainId}/{address}"
tags: ["Verify Contracts"]
---

# Verify contract via similarity search

`POST /v2/verify/similarity/{chainId}/{address}`

Starts a verification job that searches the Sourcify database for contracts whose
runtime bytecode is similar to the contract deployed at the given address. The job will
attempt to verify against each candidate until a match is found or the candidate list is exhausted.

## Path parameters

- `chainId` 31318 | 42431 | 4217, required
- `address` string, required

## Request body

- object
  - `creationTransactionHash` string — The hash of the transaction that created this contract. Optional.

## Response `202`

Successfully submitted the verification. The server started to process the verification. 

You can follow the verification status via the returned `verificationId` at `GET /v2/verify/{verificationId}`

- object
  - `verificationId` string, uuid, required

## Other responses

- `400` — Bad request from the client
- `409` — The contract is already verified
- `429` — The contract is already being verified. Jobs older than 5 minutes are considered stale and automatically expired, allowing a retry.
- `500`

## Changes

- **2026-03-09** `eef63cd83966` — 2 breaking, 1 warning, 6 info
  - the `path` request parameter `chainId` was restricted to a list of enum values
  - for the `path` request parameter `chainId`, the type changed from `string` to `integer`
  - changed the pattern of the `path` request parameter `address` from `(\b0x[a-fA-F0-9]{40}\b)` to `^0x[a-fA-F0-9]{40}$`
  - added the new enum value `31318.00` to the `path` request parameter `chainId`
  - …5 more
- **2025-12-17** `f02ddb386819` — 6 breaking, 3 warning, 1 info
  - removed the enum value `31318.00` from the `path` request parameter `chainId`
  - removed the enum value `4217.00` from the `path` request parameter `chainId`
  - removed the enum value `42431.00` from the `path` request parameter `chainId`
  - for the `path` request parameter `address`, the minLength was increased from `0` to `42`
  - …6 more

[Change history](https://skmtc.dev/tempoxyz/apis/contract-verification-api/changes/v2/verify/similarity/:chainId/:address/post.md)

---

[API](https://skmtc.dev/tempoxyz/apis/contract-verification-api.md) · [All operations](https://skmtc.dev/tempoxyz/apis/contract-verification-api/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/tempoxyz/contract-verification-api/revisions/a76585f33723/schema)