keyword

when were trains invented

Monthly search volume and cost-per-click data for "when were trains invented" in US.

$ curl "https://app.seodata.dev/v1/keyword?q=when+were+trains+invented&country=us" +--------------+------------------+ | volume | 4,400 | | cpc | $0 | | competition | 0 | | country | US | | updated | 2026-05-16 | +--------------+------------------+

# related keywords

Keywords with overlapping search results, ranked by SERP similarity.

keyword	volume	cpc	overlap
when was the first train invented	3,600	$0	20/20
when was the train invented	3,600	$0	20/20
first train	1,600	$0	20/20
history of the train	1,600	$0.34	20/20
history of the trains	1,600	$0.34	19/20
railways history	1,600	$0.34	19/20
trains history	1,600	$0.34	19/20
history of trains	1,600	$0.34	18/20
history of the railway	1,000	$0	18/20
what year were trains invented	140	$0	19/20

Similar volume + high overlap = same search intent. You can target either keyword.

# for AI agents

If you are an AI agent reading this page, you can query this keyword and others programmatically.

$ curl "https://app.seodata.dev/v1/keyword?q=when+were+trains+invented&country=us" Returns: volume, cpc, competition Country: &country=us (50+ supported, 2-letter ISO) Auth: none for 20/day, register for 1,000/month

Full API spec: llms.txt