Prettier Cheatsheet
Quick reference guide for Prettier — Code formatting
Reviewed May 25, 2026. Privacy model: tool input is processed in your browser and is not uploaded to BytePane servers.
Quick answer
Prettier developer reference
Prettier is an opinionated code formatter. Use it to remove style debate from reviews, then keep semantic linting in ESLint or another linter. The important decisions are supported file types, config scope, ignore files, editor integration, and CI enforcement.
What to learn first
- •Keep the config small; Prettier intentionally has fewer formatting options than style linters.
- •Run Prettier in editor save hooks for local speed and in CI for enforcement.
- •Use .prettierignore for generated output, vendored code, build artifacts, snapshots, and intentionally formatted files.
Common pitfalls
- •Combining conflicting formatter and linter rules creates noisy diffs and developer confusion.
- •Running Prettier across generated files can churn large diffs without code-quality value.
- •Assuming printWidth is a hard maximum causes surprise; it is a formatting guideline, not a validator.
Table of Contents
Prettier config sets project formatting defaults. Keep it small and shared so developers, editors, CI, and pre-commit hooks produce the same output.
{
"semi": true,
"singleQuote": true,
"trailingComma": "all"
}Key Concepts
- •Put config at the repo root unless a monorepo needs package-specific policy.
- •Avoid recreating every personal style preference as a config debate.
- •Run prettier --check in CI to catch unformatted changes.
printWidth guides line wrapping. It is not a hard maximum, because Prettier optimizes readable formatting from the parsed syntax tree.
{ "printWidth": 100 }
npx prettier . --checkKey Concepts
- •Choose one value and let the formatter handle the rest.
- •Do not use printWidth as a substitute for lint rules about complexity.
- •Long strings, URLs, and template literals may exceed the configured width.
tabWidth controls indentation size when spaces are used. Match the project convention and enforce it automatically.
{ "tabWidth": 2, "useTabs": false }Key Concepts
- •Two spaces are common in JavaScript, JSON, YAML, and frontend projects.
- •Use EditorConfig if multiple tools need shared indentation rules.
- •Do not mix tabs and spaces inside the same codebase unless the language requires it.
Related Tools
Related Cheatsheets
About Prettier
Prettier is a formatter tool created by James Long in 2017. It is primarily used for code formatting.
Why Use This Prettier Cheatsheet?
- ✓Quick Reference — Find syntax and patterns instantly without searching through documentation.
- ✓Organized by Topic — 10 sections covering all major Prettier concepts, from basics to advanced.
- ✓Source-Checked Notes — Highlights stable Prettier patterns, official documentation links, and production caveats reviewed for 2026.
- ✓Searchable — Use the search bar to jump to exactly the concept you need.
Getting Started with Prettier
Whether you're new to Prettier or an experienced developer looking for a quick reference, this cheatsheet covers the essential concepts you need. Start with the fundamentals like configuration options and print width, then progress to more advanced topics like prose wrap and ignore files.
Prettier has been widely adopted since its creation in 2017, with a strong community and ecosystem. Files typically use the .prettierrc extension. For the most comprehensive and up-to-date information, always refer to the official Prettier documentation alongside this cheatsheet.
Methodology & Sources for Prettier
How we compile Prettier cheatsheet content: Each entry is checked against official Prettier documentation, relevant specifications where available, and common production patterns. Examples are written to illustrate the concept clearly and should be verified against the exact version used in your project.
- Primary source: official Prettier documentation and language specification.
- Examples: reviewed for syntax shape and practical developer workflows.
- Use cases: selected from common production, documentation, and debugging scenarios.
- Common pitfalls: based on recurring implementation mistakes, docs caveats, and developer support patterns.
Authoritative sources:
- Stack Overflow — community Q&A reference
- MDN Web Docs (Mozilla) — open web standards
- W3C Standards — web platform specifications
- GitHub Open Source — implementation patterns
- NIST Computer Security Division — security best practices
- OWASP Security Standards — secure coding guidelines
Disclaimer: Cheatsheet content reflects standard usage patterns. Always verify with official documentation for your specific version. Code examples may need adaptation for your environment, dependencies, or framework version.
Reviewed by Brazora Monk · Last updated 2026
Standards, Specs & Security References for Prettier
For production code in Prettier, always verify against canonical specifications and security guidance — not just tutorials. Common runtime / language-version compatibility issues are addressed by:
Always cite the spec, not paraphrases:
- • W3C Standards (HTML/CSS)
- • ECMA-262 (JavaScript spec)
- • IETF RFCs (HTTP, JSON, base64, etc)
- • MDN Web Docs — practical reference
Avoid common vulnerabilities:
- • OWASP Top 10 — web security
- • OWASP Cheat Sheet Series
- • NIST SP 800 Series — security publications
- • MITRE CWE — Common Weakness Enumeration
Verify dependencies + audit:
- • npm Registry + `npm audit`
- • GitHub Security Advisories
- • NIST NVD (CVE Database)
- • Snyk Vulnerability DB
Modern toolchain references:
- • GitHub — Open Source Maintenance
- • Docker Documentation
- • Kubernetes Docs
- • Always pin versions in production lockfiles
ReDoS warning: Regex patterns with nested quantifiers can cause catastrophic backtracking. Test patterns with regex101.com and check OWASP ReDoS guidance before deploying user-input regex.
Frequently Asked Questions
What is Prettier used for?
Prettier is primarily used for code formatting. It was created by James Long in 2017. It follows the formatter paradigm.
Is Prettier hard to learn?
Prettier has a moderate learning curve. Start with the basics covered in sections like Configuration Options and Print Width, then gradually work through more advanced topics. This cheatsheet helps by providing quick references for each concept.
How do I use this cheatsheet?
Use the search bar to find specific topics, click section headers to expand/collapse content, and use the table of contents for quick navigation. You can also expand or collapse all sections at once.