[Home](./index.md) > [puppeteer](./puppeteer.md) > [ExecutionContext](./puppeteer.executioncontext.md) > [evaluate](./puppeteer.executioncontext.evaluate.md)
## ExecutionContext.evaluate() method
Signature:
```typescript
evaluate(pageFunction: Function | string, ...args: unknown[]): Promise;
```
## Parameters
| Parameter | Type | Description |
| --- | --- | --- |
| pageFunction | Function \| string | a function to be evaluated in the executionContext |
| args | unknown\[\] | argument to pass to the page function |
Returns:
Promise<ReturnType>
A promise that resolves to the return value of the given function.
## Remarks
If the function passed to the `executionContext.evaluate` returns a Promise, then `executionContext.evaluate` would wait for the promise to resolve and return its value. If the function passed to the `executionContext.evaluate` returns a non-serializable value, then `executionContext.evaluate` resolves to `undefined`. DevTools Protocol also supports transferring some additional values that are not serializable by `JSON`: `-0`, `NaN`, `Infinity`, `-Infinity`, and bigint literals.
## Example 1
```js
const executionContext = await page.mainFrame().executionContext();
const result = await executionContext.evaluate(() => Promise.resolve(8 * 7))* ;
console.log(result); // prints "56"
```
## Example 2
A string can also be passed in instead of a function.
```js
console.log(await executionContext.evaluate('1 + 2')); // prints "3"
```
## Example 3
[JSHandle](./puppeteer.jshandle.md) instances can be passed as arguments to the `executionContext.* evaluate`:
```js
const oneHandle = await executionContext.evaluateHandle(() => 1);
const twoHandle = await executionContext.evaluateHandle(() => 2);
const result = await executionContext.evaluate(
(a, b) => a + b, oneHandle, * twoHandle
);
await oneHandle.dispose();
await twoHandle.dispose();
console.log(result); // prints '3'.
```