Tools · Comparison

Knowly vs Perplexity AI vs StudyforCitizenship

All three are research tools. Here is what separates them.

	Knowly	Perplexity AI	StudyforCitizenship
What it is	Everyone is building AI to execute work. Knowly is building AI to grow the brain itself — a proactive second brain that guides your whole learning journey and turns what you save into understanding that stays.	AI-powered search engine providing accurate, sourced answers using LLMs and real-time web search.	A study guide for US Naturalization Test, in every language.
Category	Research	Research	Research
Pricing	Freemium	Freemium · $20/mo	Paid
How it bills	Not published	Flat monthly	Not published
Free tier	Yes	Yes	No
Rating	Not yet rated	4.6 from 5,400 reviews	Not yet rated
Features	—	Real-time web search Cited sources Pro Search deep research File analysis Image search Code execution Collections API access	—
What works	—	Accurate with citations Real-time information Excellent for research Clean interface Generous free tier	Sits in Research, one of the better-covered categories here — easy to compare
What does not	—	Pro features behind paywall Sometimes shallow answers Limited creative tasks Fewer integrations	No free tier — it has to be paid for before it can be tried Does not publish a price on its own site, so the cost is only clear after signing up 44 other tools in this catalogue claim to do the same job 12 tools in the same category have a free tier