# Use sentence-style capitalization in headings (EK00037)

import { Aside, Badge } from '@astrojs/starlight/components';

Sentence-style capitalization capitalizes only the first word and any proper nouns in a heading, which reads cleanly and keeps every heading in your documentation consistent. EkLine flags a heading written in title case and suggests sentence case (rule EK00037).

## Why use sentence-style capitalization in documentation?

Title case forces a decision about every word — which ones to capitalize — and different writers make that call differently, so a set of headings drifts out of sync. Sentence case removes the guesswork: capitalize the first word and proper nouns, lowercase the rest. The result reads like natural prose and matches the style guides most software documentation follows.

## What EkLine flags

EK00037 matches a heading written in title case instead of sentence case.

- ❌ **Incorrect:** Getting Started With Authentication
- ✅ **Correct:** Getting started with authentication
- ❌ **Incorrect:** Configure Your Project
- ✅ **Correct:** Configure your project

## How to fix

Lowercase every word in the heading except the first word and any proper nouns.

<Aside type="note">
Keep proper nouns and product names capitalized. Write "Set up GitHub access", not "Set up github access".
</Aside>

## FAQ

### What is sentence-style capitalization?

Sentence-style capitalization, or sentence case, capitalizes only the first word of a heading and any proper nouns. For example, "Getting started with authentication" instead of "Getting Started With Authentication".

### What is the difference between sentence case and title case?

Sentence case capitalizes the first word and proper nouns only, while title case capitalizes most words in the heading. Sentence case reads like natural prose and removes the guesswork about which words to capitalize.

## Rule details

| Property | Value |
|----------|-------|
| Rule ID | `EK00037` |
| Category | Consistency |
| Default severity | <Badge text="Error" variant="danger" /> |
| Enabled by default | Yes |

## Ignore this rule

To keep a title-case heading on one line, add an inline comment:

```markdown
<!-- ekline-ignore-next-line EK00037 -- keeps the exact wording of a cited title -->
## The Chicago Manual of Style
```

To disable the rule across your project, add it to the `ignore` list in your [configuration file](/reviewer/configuration/ignoring-rules/#ignore).

## Related rules

- [EK00002](/reviewer/rules/ek00002/) — Avoid acronyms in titles or headings
- [EK00023](/reviewer/rules/ek00023/) — Avoid end punctuation in headings