---
Source: https://docs.microblink.com/verify/certainty-level
Title: Certainty level
Description: How certainty level expresses Verify's confidence in a check result
---

# Certainty level

`CertaintyLevel` is the measure of confidence that BlinkID Verify has in the result of a [check](./check.md).

It can be `Low`, `Medium`, or `High`.
If a check was not performed, the value is `NotPerformed`.

```json
"checks": [
  {
    "name": "ExtractedDataCheck",
    "result": "Pass",
    // highlight-next-line
    "certaintyLevel": "High",
    "type": "DetailedCheck",
```

## Why certainty varies

Some checks are inherently limited in how certain they can be.
For example, a check that flags suspiciously common names can never be fully certain—a document holder could genuinely be named "John Smith".
When such checks fail, they never do so with a `High` certainty level.

Other checks can draw on multiple independent factors.
The more of those factors are present and consistent, the higher the certainty level.
Conversely, if too few factors are available—for example, because image quality is poor—the certainty level drops.

## What to do with a low certainty level

A low certainty level on a failed check is a signal that the result may benefit from human review.
If your workflow supports it, route documents with low-certainty failures to [manual review](/verify/configuration#manual-review-strategy-and-sensitivity) rather than rejecting them outright.


Last updated on Jun 18, 2026