How to Use Collapsible Sections in GitHub Markdown

How to Build Interactive Collapsible Accordions in GitHub Markdown (<details>)

Direct Answer (TL;DR)

To create a collapsible dropdown section in GitHub Markdown, wrap your content in an HTML <details> tag and define the clickable title using a nested <summary> tag. GitHub's Markdown processor renders this as an accessible, zero-JavaScript interactive accordion element natively.

Solving README Information Overload

A common flaw in developer profiles is infinite scroll syndrome. Listing 20 repositories, 15 certifications, and detailed logs in one flat document exhausts readers.

HTML <details> accordions allow you to maintain comprehensive documentation while preserving a clean, concise executive summary for busy recruiters.

Production Accordion Implementation Code

### 📜 Professional Certifications & Accreditations

<details>
<summary><b>Click to expand verified cloud & security credentials (6)</b></summary>

<br/>

| Certification Name | Issuing Authority | Verification ID | Valid Through |
| :--- | :--- | :--- | :--- |
| **AWS Solutions Architect - Professional** | Amazon Web Services | AWS-PSA-89412 | Dec 2028 |
| **Certified Kubernetes Administrator (CKA)** | CNCF / Linux Foundation | LF-CKA-10294 | Aug 2027 |
| **Google Cloud Professional Cloud Architect** | Google Cloud | GCP-PCA-44910 | Jan 2028 |

</details>

Frequently Asked Questions

❓ Can I make an accordion open by default?

Yes! Add the open attribute: <details open>. GitHub will render the accordion pre-expanded while allowing visitors to collapse it.

❓ Can accordions be nested inside each other?

Yes. GitHub Flavored Markdown supports multi-level nested <details> tags. Ensure proper indentation and matching closing tags.