Which Naming Style to Use for Code and URLs

By Case Modify Editorial · Published October 22, 2026 · Updated October 22, 2026

One label, five destinations. Map a product name to the style each layer of the stack actually expects.

Start from the destination, not the slogan

camelCase, PascalCase, snake_case, kebab-case, and CONSTANT_CASE all remove spaces. They disagree on the first letter and the separator. Pick the style the file already uses. A JavaScript variable, a React component, a Python function, a URL, and an environment variable should not share one spelling.

One label, five results

Take the label Order Line Item. A JavaScript variable or JSON key becomes orderLineItem. A class or React component becomes OrderLineItem. A Python function or SQL column becomes order_line_item. A URL slug or CSS class becomes order-line-item. An environment variable becomes ORDER_LINE_ITEM. Convert the symbol, then proofread it. Do not run the whole marketing sentence through the converter.

Acronyms need a second look

Mechanical conversion lowercases or capitalizes by word boundaries. HTTP response code may become httpResponseCode, HttpResponseCode, or http_response_code. Some teams keep the acronym in caps inside PascalCase (HTTPResponse) and some do not. The team style guide wins. The converter gives you a consistent draft.

Do not mix styles in one payload

An API that returns userId next to user_name forces every client to guess. Document one style per boundary: camelCase in JSON, snake_case in the database, kebab-case in the URL. Convert at the boundary instead of letting both spellings leak into the same object.

Pairwise guides for the close calls

When two styles look similar, read the narrower comparison. PascalCase versus camelCase is the first-letter rule for types versus variables. kebab-case versus snake_case is the hyphen versus underscore rule for URLs versus columns. This page is the map. Those posts are the arguments.