seodata.dev

keyword

when was federal income tax started

Monthly search volume and cost-per-click data for "when was federal income tax started" in US.

$ curl "https://app.seodata.dev/v1/keyword?q=when+was+federal+income+tax+started&country=us" +--------------+------------------+ | volume | 2,900 | | cpc | $3.12 | | competition | 0.01 | | country | US | | updated | 2026-06-15 | +--------------+------------------+

# related keywords

Keywords with overlapping search results, ranked by SERP similarity.

keyword volume cpc overlap
income tax when did it start 3,600 $2.27 14/20
when federal income tax started 2,400 $2.17 17/20
when did income tax start in america 1,900 $2.9 14/20
income tax history 1,300 $3.28 18/20
when did taxation start 1,000 $3.39 19/20
income taxes history 1,000 $2.27 18/20
who invented taxes 1,000 $0 14/20
taxes history 880 $2.51 16/20
history of taxes 480 $2.15 16/20
why was federal income tax started 20 $0 14/20

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+was+federal+income+tax+started&country=us" Returns: volume, cpc, competition Country: &country=us (50+ supported, 2-letter ISO) Auth: none for 20/day, register for 500/month, $4.99/mo unlimited

Full API spec: llms.txt