Google Trends
Compare how search interest in topics changes over time and by region
Google Trends shows how interest in a search term or topic changes over time and differs between countries and regions. Values are relative, on a scale from 0 to 100, where 100 is the peak interest for the chosen time and place; they are not search volumes. You can compare up to five terms at once and see related topics and queries that are rising.
For SEO and content planning, Trends is useful for spotting seasonality before you plan content, comparing which of two phrasings people use more, checking whether a topic is growing or fading, and finding regional differences. Because the numbers are relative, pair it with a keyword tool when you need an idea of absolute demand.