How to convert visualforce page into excel format in Salesforce?

Hello,

By simply modifying the ContentType attribute on the <apex:page> tag, your Visualforce page code will automatically generate an Excel document. For example, the following code will create a table of Contact data for a given Account. After # in the contentType attribute value, it is the name of the excel file that will be generated and you also need to mention the file extension like .xls . For successfully running the below code you need to provide the valid account id in URL.

sample Vf code:-

<apex:page standardController="Account" contenttype="application/vnd.ms-excel#Demo Example.xls">
<apex:pageBlock title="Hello {!$User.FirstName}!">
You are viewing the {!account.name} account.
</apex:pageBlock>
<apex:pageBlock title="Contacts">
<apex:pageBlockTable value="{!account.Contacts}" var="contact">
<apex:column value="{!contact.Name}"/>
<apex:column value="{!contact.Email}"/>
<apex:column value="{!contact.Phone}"/>
</apex:pageBlockTable>
</apex:pageBlock>
</apex:page>