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Domain control validation backoff schedule

Domain control validation (DCV) has to happen before a Certificate Authority (CA) will issue a certificate for a domain. If DCV fails during issuance or renewal, Cloudflare automatically retries it on a schedule.

If you use Delegated DCV or if Cloudflare automatically performs DCV for you, this page is only informational. If you have to manually perform DCV, consider the following sections about the validation schedule and remember that DCV tokens have a fixed validity period.


​​ DCV tokens validity

The DCV process relies on tokens that are generated by the issuing Certificate Authority. These tokens have a validity period defined by each CA:

  • DigiCert - 30 days
  • Google Trust Services - 14 days
  • Let’s Encrypt - 7 days

After this period, DCV tokens expire as dictated by the CA/B Baseline Requirements, and new, valid tokens must be placed.


​​ Successive checks function

Cloudflare caps the check backoff to a maximum of four hours to avoid the function growing exponentially, which would result in large gaps between checks towards the end of the month.


now() + min((floor(60 * pow(1.05, retry_attempt)) * INTERVAL '1 second'), INTERVAL '4 hours')

​​ Capped attempts reference table

As presented in the following table, most of the checks take place on the first day after the DCV token is generated.

In manual processes, it is possible that you fall behind schedule when you place the token, meaning that it may not be validated immediately.

In automatic processes, most validations complete within the first five minutes, unless there is a setup misconfiguration.

Retry Attempt In Seconds In Minutes In Hours
0 60 1.000 0.016667
1 63 1.050 0.017500
2 66 1.100 0.018333
3 69 1.150 0.019167
4 72 1.200 0.020000
5 76 1.267 0.021111
6 80 1.333 0.022222
7 84 1.400 0.023333
8 88 1.467 0.024444
9 93 1.550 0.025833
10 242 4.033 0.067222
11 279 4.650 0.077500
12 321 5.350 0.089167
13 369 6.150 0.102500
14 424 7.067 0.117778
15 488 8.133 0.135556
16 561 9.350 0.155833
17 645 10.750 0.179167
18 742 12.367 0.206111
19 853 14.217 0.236944
20 981 16.350 0.272500
21 1129 18.817 0.313611
22 1298 21.633 0.360556
23 1493 24.883 0.414722
24 1717 28.617 0.476944
25 1975 32.917 0.548611
26 2271 37.850 0.630833
27 2612 43.533 0.725556
28 3003 50.050 0.834167
29 3454 57.567 0.959444
30 3972 66.200 1.103333
31 4568 76.133 1.268889
32 5253 87.550 1.459167
33 6041 100.683 1.678056
34 6948 115.800 1.930000
35 7990 133.167 2.219444
36 9189 153.150 2.552500
37 10567 176.117 2.935278
38 12152 202.533 3.375556
39 13975 232.917 3.881944
40 14400 240.000 4.000000
41 14400 240.000 4.000000
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119 14400 240.000 4.000000