> For the complete documentation index, see [llms.txt](https://docs.docbits.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.docbits.com/end-user-and-partner-section/end-user-section/validation-screen/automatic-checks-on-the-validation-screen.md).

# Automatic Checks on the Validation Screen

## Overview

By default, specific fields in the field validation process are automatically checked by verifying their values using formulas based on other extracted values. On this page, you can find the forms used for these automatic calculations.

You can always verify the formula used by hovering over the info icon.

<figure><img src="/files/slunqd6r4Q5scH89zuyz" alt=""><figcaption></figcaption></figure>

<mark style="color:red;">**Note:**</mark> The info icon is only visible if a value has been extracted for the corresponding field.

## Formulars for automatic checks:

### Net amount:

```
Net amount = Tax amount * 100 / Vat rate 
```

### Vat rate:

```
Vat rate = Tax amount * 100 / Net amount 
```

### Tax amount:

```
Tax amount = Net amount + Vat rate / 100
```

### Net amount reduced:

```
Net amount reduced = Reduced Tax amount * 100 / Vat rate reduced
```

### Vat rate reduced:

```
Vat rate reduced = Reduced Tax amount * 100 / Net amount reduced
```

### Tax amount reduced:

```
Tax amount reduced = Reduced Tax amount + Vat rate reduced / 100
```

### Total net amount:

```
Total net amount = Net amount + Reduced Tax amount + Net amount free
```

### Total net amount US:

```
Total net amount US = Net amount + Shipping charges + Misc. charges + Additional amount
```

### Total tax amount:

```
Total tax amount = Tax amount + Reduced Tax amount + Tax amount free 
```

### Total amount:

```
Total amount = Net amount + Tax Amount
```

<mark style="color:red;">**Note:**</mark> If the extracted value and the validated value do not match, the document cannot be processed further. An **Amounts Mismatch** error will appear for the corresponding field.


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://docs.docbits.com/end-user-and-partner-section/end-user-section/validation-screen/automatic-checks-on-the-validation-screen.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.