How to get unlimited requests from Google custom search api
You will need to register for invoicing:
Any use outside the free use quota will fail unless you sign up for billing. Once you've turned on billing, you will continue to receive 100 free requests per day. However, you will be billed for all additional requests at a rate of $ 5 per 1,000 requests, up to 10,000 requests per day. If you need an additional quota, please request an additional quota from the console.
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