> For the complete documentation index, see [llms.txt](https://guide.form.gov.sg/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://guide.form.gov.sg/user-guides/advanced-guide/logic.md).
# Logic
You can show or hide fields or disable form submission for invalid answers depending on user selection/input. See examples on how to apply conditional logic to your form below:
{% embed url="" %}
{% embed url="" %}
{% tabs %}
{% tab title="Text Tutorial" %}
### Text Tutorial: Logic
**Step 1: To the left of your form, click on this symbol** .
**Step 2: Press the "Add Logic" button.**
**Step 3: Customise Logic**
* **A - Choose allowed fields to apply logic** -> Radio, Rating, Number, Decimal, Dropdown and Yes/No fields only.
* **B - Choose condition** -> Depending on field chosen, conditions will differ.
* **C - Add multiple conditions**
* **D - Choose what happens** -> Choose what fields to display or disable submission
* **E - Finish creating logic**
{% endtab %}
{% endtabs %}
---
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```
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```
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