These are “SEO Tools” I use as part of my ongoing niche discovery and research. I am providing them here for your reference in case you would like to use them too.
I rarely trust information I get from one source, so I like to confirm things across a few tools. Specifically related to keyword search volume, competitiveness, CPC, and complexity. If a few tools report similar data, it can probably be trusted as fairly accurate.
Serpstat All-In-One SEO Platform is the one of the SEO tools that I always have open in a browser tab. My subscription allows me to do 300 keyword searches in a day, which is more than enough for me (since I am a one man show).
Google Keyword Planner (part of Google Ads) Registration required, but you can log in with your gmail account. Google is always refining this site, and the Keyword Tool is sometimes hard to find. Many tutorials available across the web.
Keyword Explorer on MOZ I love MOZ, but as of now am not a subscriber. They have a free tier that is useful, and I’ll use the various tools available to look for links, alternate keywords, and search volume.