Best keyword research tools
The honest way to compare keyword tools is by where their data comes from. Here's what each well-known option really gives you, including us.
| Tool | Cost | Data behind it | Best for | Limits |
|---|---|---|---|---|
| Google Search Console | Free | Your real impressions, clicks and positions | Finding what you already rank for; the most trustworthy numbers | Only your own site; no new-keyword discovery |
| Google Keyword Planner | Free with an Ads account | Google Ads search volume and bid ranges | Volume sourced from Google itself | Broad ranges unless you spend; merges close variants; built for ads |
| Google Trends | Free | Relative interest over time and region | Seasonality and comparing terms | No absolute numbers |
| Ahrefs | Paid; free Webmaster Tools for your own sites | Own keyword and backlink index; KD from referring domains | Difficulty, traffic potential, competitor research | Cost; estimates differ from other tools |
| Semrush | Paid; limited free account | Own keyword database; PPC and competitor data | All-in-one SEO and PPC workflows | Cost; estimates differ from other tools |
| Moz Keyword Explorer | Paid; limited free queries | Own index; difficulty, priority score | Clear prioritisation metrics | Smaller free allowance |
| AnswerThePublic | Limited free searches | Autocomplete-based questions and prepositions | Question ideas at a glance | Few free searches per day |
| KeywordForge | Free, no account | No search data by design; AI and rule-based language tools | Ideation, long-tail, clustering, intent, titles, briefs, exports | No volumes, difficulty or backlinks: bring them from above |
Plans and allowances change often; check each vendor's pricing page for current limits. Last reviewed September 2026.
How to choose
If you're a blogger or small business on no budget
Use Search Console for what you already rank for, Keyword Planner for rough volumes and Trends for seasonality. Do the ideation, cleaning, clustering and intent work with free tools like ours. You'll get 80% of a paid workflow; what you give up is precise volumes and competitor backlink data.
If you do SEO for clients or a growing site
A paid suite pays for itself in time: Ahrefs and Semrush both combine large keyword databases, difficulty scores, SERP history and competitor research. Pick one and stick with it, because their numbers aren't comparable with each other.
If you run paid search
Keyword Planner is the source of truth for Google Ads, and the keyword mixer will build match-type lists for your ad groups.
Red flags in “free keyword tools”
- Precise volumes and difficulty for any keyword, unlimited, with no stated data source.
- Every keyword scored “easy” or “low competition”.
- Volumes that don't change between countries or months.
That is why KeywordForge shows no numbers at all. We'd rather hand you a prioritiser that works with real data than decorate a list with guesses.
Questions people ask
What is the best keyword research tool for SEO?
For most professionals, a paid suite with its own search and backlink index (Ahrefs or Semrush) is the most complete option. For budget-conscious bloggers, the free combination of Google Search Console, Google Keyword Planner, Google Trends and a free ideation and clustering tool covers most of the job.
What is the best free keyword research tool?
Google Search Console, because it shows real impressions for your own site. For finding new keywords, Google Keyword Planner gives Google-sourced volume ranges, and free tools like KeywordForge handle ideation, clustering and intent without pretending to have volume data.
Is there a free alternative to Google Keyword Planner?
For ideas, yes: many free generators. For volumes, the honest alternatives are limited free lookups in Ahrefs, Semrush, Moz or Ubersuggest, and Search Console for your own queries. Be wary of free tools showing unlimited precise volumes without saying where they come from.
Does KeywordForge replace Ahrefs or Semrush?
No. It has no search or backlink index. It covers the language work (ideas, long-tail, clustering, intent, titles, briefs) for free, and is designed to sit alongside whichever volume source you use.