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[Home ](./index.md ) > [puppeteer ](./puppeteer.md ) > [Page ](./puppeteer.page.md ) > [evaluate ](./puppeteer.page.evaluate.md )
## Page.evaluate() method
< b > Signature:< / b >
```typescript
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evaluate< T extends EvaluateFn > (pageFunction: T, ...args: SerializableOrJSHandle[]): Promise< UnwrapPromiseLike < EvaluateFnReturnType < T > >>;
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```
## Parameters
| Parameter | Type | Description |
| --- | --- | --- |
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| pageFunction | T | a function that is run within the page |
| args | [SerializableOrJSHandle ](./puppeteer.serializableorjshandle.md )<!-- --> \[\] | arguments to be passed to the pageFunction |
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< b > Returns:< / b >
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Promise< [UnwrapPromiseLike](./puppeteer.unwrappromiselike.md)<!-- --> < [EvaluateFnReturnType](./puppeteer.evaluatefnreturntype.md)<!-- --> < T> > >
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the return value of `pageFunction` <!-- --> .
## Remarks
Evaluates a function in the page's context and returns the result.
If the function passed to `page.evaluteHandle` returns a Promise, the function will wait for the promise to resolve and return its value.
## Example 1
```js
const result = await frame.evaluate(() => {
return Promise.resolve(8 * 7);
});
console.log(result); // prints "56"
```
You can pass a string instead of a function (although functions are recommended as they are easier to debug and use with TypeScript):
## Example 2
```
const aHandle = await page.evaluate('1 + 2');
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```
To get the best TypeScript experience, you should pass in as the generic the type of `pageFunction` <!-- --> :
```
const aHandle = await page.evaluate< () => number>(() => 2);
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```
## Example 3
[ElementHandle ](./puppeteer.elementhandle.md ) instances (including [JSHandle ](./puppeteer.jshandle.md )<!-- --> s) can be passed as arguments to the `pageFunction` <!-- --> :
```
const bodyHandle = await page.$('body');
const html = await page.evaluate(body => body.innerHTML, bodyHandle);
await bodyHandle.dispose();
```