`FormData` is the browser-standard object used to represent values submitted by an [HTML](/courses/html) form. When a form calls a Server Action, [Next.js](/courses/nextjs) and [React](/courses/reactjs) automatically provide the submitted form data to that action. ### Example Form ```jsx ``` The Server Action can read the fields: ```javascript 'use server'; export async function createProfile(formData) { const name = formData.get('name'); const age = formData.get('age'); const role = formData.get('role'); console.log({ name, age, role }); } ``` ### Form Values Are Usually Strings Even though this input uses: ```jsx ``` `formData.get('age')` normally produces a string such as: ```javascript '25' ``` not: ```javascript 25 ``` Convert it explicitly: ```javascript const age = Number(formData.get('age')); ``` and validate the result before using it. ### Reading Multiple Values Suppose several checkboxes share the same name: ```jsx React Next.js ``` Use: ```javascript const skills = formData.getAll('skills'); ``` The result might be: ```javascript ['react', 'nextjs'] ``` ### Converting FormData to an Object For simple forms: ```javascript const values = Object.fromEntries(formData.entries()); ``` can produce something like: ```javascript { name: 'Asif', age: '25', role: 'author' } ``` Be careful with repeated fields because converting directly to an object can lose multiple values with the same key. Use `getAll()` when a field intentionally has multiple values. ### Missing Values This: ```javascript formData.get('email'); ``` can return `null` if the value does not exist. Therefore, never assume that a required field is present just because your frontend contains an input for it. ### Interview-Ready Answer Server Actions receive submitted form values through the standard `FormData` API. Use `get()` for a single field and `getAll()` for repeated values. Form values commonly arrive as strings, so numeric and structured values should be converted and validated explicitly before being used.