Verify Blockchain Anchors

Overview

Anchor verification confirms two things:

Anchor integrity (valid) — the Merkle root stored in the anchor matches the Merkle root recomputed from the underlying events.
Anchor chain integrity (chain_valid) — the previous_anchor_hash correctly references the preceding anchor.

If either check fails, your audit trail may have been tampered with between event ingestion and blockchain submission.

List Anchors

Retrieve your workspace’s blockchain anchors:

curl https://getimmutable.dev/api/v1/anchors?limit=10 \
  -H "Authorization: Bearer imk_your_api_key_here"

import { ImmutableClient } from "getimmutable";

const client = new ImmutableClient({
  apiKey: "imk_your_api_key_here",
  baseUrl: "https://getimmutable.dev",
});

const anchors = await client.getAnchors(10);

from getimmutable import ImmutableClient

client = ImmutableClient(
    api_key="imk_your_api_key_here",
    base_url="https://getimmutable.dev",
)

anchors = client.get_anchors(limit=10)

use GetImmutable\AuditLog;

$anchors = AuditLog::client()->getAnchors();

Get Anchor Detail

Retrieve a single anchor with additional fields (first_event_hash, last_event_hash):

curl https://getimmutable.dev/api/v1/anchors/anc_abc123 \
  -H "Authorization: Bearer imk_your_api_key_here"

const anchor = await client.getAnchor("anc_abc123");
console.log(anchor.data.explorer_url);
// https://basescan.org/tx/0x7a8b...

anchor = client.get_anchor("anc_abc123")
print(anchor["data"]["explorer_url"])

$anchor = AuditLog::client()->getAnchor('anc_abc123');

Verify an Anchor

The verify endpoint recomputes the Merkle root from the underlying events and checks the anchor chain:

curl https://getimmutable.dev/api/v1/anchors/anc_abc123/verify \
  -H "Authorization: Bearer imk_your_api_key_here"

const result = await client.verifyAnchor("anc_abc123");

if (result.data.valid && result.data.chain_valid) {
  console.log("Anchor verified. Merkle root and chain are intact.");
} else {
  console.error("Anchor verification failed!", result.data);
}

result = client.verify_anchor("anc_abc123")

if result["data"]["valid"] and result["data"]["chain_valid"]:
    print("Anchor verified.")
else:
    print("Verification failed!", result["data"])

$result = AuditLog::client()->verifyAnchor('anc_abc123');

if ($result['data']['valid'] && $result['data']['chain_valid']) {
    Log::info('Anchor verified');
} else {
    Log::critical('Anchor verification failed', $result['data']);
}

Verify Response

{
  "data": {
    "anchor_id": "anc_abc123",
    "merkle_root": "9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08",
    "valid": true,
    "chain_valid": true,
    "expected": "9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08",
    "actual": "9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08",
    "events_count": 1247,
    "tx_hash": "0x7a8b9c0d1e2f3a4b5c6d7e8f9a0b1c2d3e4f5a6b7c8d9e0f1a2b3c4d5e6f7a8b",
    "explorer_url": "https://basescan.org/tx/0x7a8b9c0d1e2f3a4b5c6d7e8f9a0b1c2d3e4f5a6b7c8d9e0f1a2b3c4d5e6f7a8b"
  }
}

Response Fields

Field	Type	Description
`anchor_id`	string	The anchor identifier
`merkle_root`	string	The 64-character hex Merkle root stored in this anchor
`valid`	boolean	Whether the recomputed Merkle root matches the stored one
`chain_valid`	boolean	Whether the `previous_anchor_hash` correctly references the preceding anchor
`expected`	string	The Merkle root recomputed from the underlying events
`actual`	string	The Merkle root stored in the anchor record
`events_count`	integer	Number of events included in this anchor’s Merkle tree
`tx_hash`	string	The blockchain transaction hash (null if not yet confirmed)
`explorer_url`	string	Direct link to the transaction on Basescan

Understanding Failures

`valid: false`

The Merkle root recomputed from the underlying events does not match the stored Merkle root. This means events were modified, inserted, or deleted after the anchor was created. The expected and actual fields show the mismatch.

`chain_valid: false`

The previous_anchor_hash does not match the expected value computed from the preceding anchor’s merkle_root and tx_hash. This means an anchor was modified, inserted into, or deleted from the anchor chain.

Verify All Anchors

To verify every anchor in your workspace:

const anchors = await client.getAnchors(100);

for (const anchor of anchors.data) {
  const result = await client.verifyAnchor(anchor.id);

  if (!result.data.valid || !result.data.chain_valid) {
    console.error(`Anchor ${anchor.id} failed verification`, {
      valid: result.data.valid,
      chain_valid: result.data.chain_valid,
      period: `${anchor.period_start} — ${anchor.period_end}`,
    });
  }
}

After verifying via the API, cross-check confirmed anchors on Basescan for fully independent verification. See Verify On-Chain.

How It Works

Verify It Yourself

Verify Blockchain Anchors

Overview

List Anchors

Get Anchor Detail

Verify an Anchor

Verify Response

Response Fields

Understanding Failures

`valid: false`

`chain_valid: false`

Verify All Anchors

​Overview

​List Anchors

​Get Anchor Detail

​Verify an Anchor

​Verify Response

​Response Fields

​Understanding Failures

​valid: false

​chain_valid: false

​Verify All Anchors

Overview

List Anchors

Get Anchor Detail

Verify an Anchor

Verify Response

Response Fields

Understanding Failures

`valid: false`

`chain_valid: false`

Verify All Anchors