Short version: there is no single “best truly free keyword tool,” but there is a best free stack + workflow for a niche site. I agree with most of what @sonhadordobosque and others said about piggybacking on competitors and using SERPs, but here’s what I’d add that people rarely talk about.
1. The one “tool” everyone sleeps on: Google Search Console
If your site is even a few weeks old and indexed, GSC is the closest thing you’ll get to a free Ahrefs clone for your own keywords.
How to use it for keyword research:
- Go to Performance → Search results
- Sort by Clicks then by Impressions
- Look for:
- Queries where you’re in positions 5–20
- Queries with impressions > 20 but almost no clicks
Those are:
- “Almost ranking” keywords you can win by:
- Improving title tags
- Adding a specific section / FAQ to the page
- Creating a small supporting post that links back
This is not just “optimize what you have.” It also gives you new content ideas:
- See a query that is only weakly related to the page?
- That’s a new article topic.
- See variants of the same question?
- That’s your content cluster.
I actually disagree a bit with the pure “forget about data, just eyeball SERPs” approach. Once GSC starts showing patterns, it is real user data, not tool-estimated noise. For a tight budget, that is gold.
2. Use People Also Ask and “Related Searches” properly
Most people just copy PAA questions and shove them as H2s. Better workflow:
- Search your seed topic in Google
- Open 5–10 PAA questions that:
- Sound like full blog post ideas
- Or are clearly subtopics for a big guide
- Drop each question into:
- Your draft outline as an H2/H3
- Or a list of future standalone posts
Then scroll to “Related searches” at the bottom:
- Treat them as:
- Supporting articles
- Or sections inside a pillar page
You do not need volume numbers if:
- There are multiple distinct PAA questions
- Related searches are tight variations
That already tells you the topic has search depth.
3. Free “volume sense” trick using multiple tools
No tool is accurate, but you can get a directional idea for free:
- Pick a candidate keyword from:
- PAA
- Related searches
- GSC
- Check it in:
- Google Keyword Planner
- Ubersuggest free
- Ahrefs’ free keyword overview
You are not looking for the number itself. You’re checking:
- Is it always “0” or “very low” everywhere
- Or do all of them show some volume and similar variants
If:
- GKP groups it with a bigger phrase
- Ubersuggest shows variants with non-zero volume
- Ahrefs shows it in phrase match or similar keywords
Then it is safe enough to target for a niche site. This is not precision; it is a “do not waste time on absolute dead ends” filter.
4. Content-angle research rather than pure keyword research
Instead of just hunting for phrases, look for angles that are under-served:
- Search your topic
- Open top 5 results
- Ask:
- Are they all generic “ultimate guides”?
- Is there a missing angle like:
- “For beginners”
- “For [specific audience]”
- “With real case studies”
- “Using free tools only”
Make your post:
- Same topic, different promise in the title and meta
- Better match to the specific pain point
You can often outrank stronger domains by being more specific and focused, even without fancy volume data.
5. Pros & cons of relying on a “best free keyword research tool” mindset
Since we’re talking about the elusive “best truly free keyword research tool right now,” here are the pros and cons of chasing a single tool versus running a stack:
Pros of a single-tool mindset:
- Simpler workflow, less overwhelming
- Easier to be consistent
- Good if you really hate juggling interfaces
Cons:
- Every free tool is rate-limited or data-limited
- You get trapped in that tool’s blind spots
- You mistake the number on screen for reality
- When the tool changes its free tier, your process dies
A stack approach (Google Search Console + SERPs + 1–2 free third-party tools) is more resilient and honestly more accurate for small sites.
6. Brief note on what @sonhadordobosque covered
They did a solid job on:
- Using competitor domains in Ubersuggest / Ahrefs free versions
- Treating SERPs as your “real” tool
- Mining Reddit and forums
The part I lean into harder is:
- Systematic use of Search Console as soon as you have any traffic
- Treating keyword research as an ongoing feedback loop, not a one-time research sprint before you publish
You do not need to obsess over the “perfect” free keyword tool. Build a small workflow, adapt it as your site grows, and let real queries from your own traffic slowly replace guesswork.