# Search volume, CPC and keyword ideas from one API call

Send a seed keyword to seo.keywords and get JSON back: monthly search volume, cost per click and competition for the seed, then a list of keyword ideas with the same numbers and a competition level. Location defaults to the United States and takes a country or a city. One RouterGrowth key, from code or from an agent.

HTML page: https://www.routergrowth.com/tools/seo/keyword-research-api
Part of: [SEO tools](https://www.routergrowth.com/tools/seo.md)

## The call

[`seo.keywords`](https://www.routergrowth.com/catalog/seo.keywords): Search volume and keyword ideas for a seed keyword.

Price on this network: $0.00021 per search plus $0.021 per call. The exact quote is shown before every run.

## What a real run returned

Run on 2026-10-19: 10 records in 0.4 s for $0.0231. Personal fields are masked. Ten ideas for invoice software in the United States: the seed has 5,400 searches a month, and a branded idea carries more volume at a lower CPC.

| keyword | volume | cpc | competition_level |
|---|---|---|---|
| zoho invoice software | 18100 | 20.54 | LOW |
| invoice and billing software | 5400 | 75.92 | MEDIUM |
| free software invoice | 4400 | 32.31 | MEDIUM |

## How to do it

1. **Get a key.** Create a RouterGrowth API key in the dashboard.
2. **POST the seed.** Send capability seo.keywords with keyword, an optional location and language, and limit.
3. **Read the seed's numbers.** volume, cpc and competition sit at the top level of the result.
4. **Work the ideas.** ideas is a list of keywords with volume, cpc, competition and competition_level, ready to sort or filter.

## Ask it like this

- Get 50 keyword ideas for invoice software in the UK and keep the ones under medium competition. (`seo.keywords`)
- Find keyword ideas for our product category, then check who ranks on Google for the top five. (`seo.keywords`, `seo.serp`)

## Connect

MCP server: `https://api.routergrowth.com/mcp`

```bash
claude mcp add --transport http routergrowth https://api.routergrowth.com/mcp
```

```bash
npm install -g routergrowth && routergrowth setup
routergrowth run -c seo.keywords -i '{"keyword": "invoice software", "limit": 10}'
```

```bash
curl -X POST https://api.routergrowth.com/v1/run \
  -H "Authorization: Bearer $ROUTERGROWTH_API_KEY" \
  -d '{"capability": "seo.keywords", "input": {"keyword": "invoice software", "limit": 10}}'
```

## Worth knowing

- **Variants share numbers.** Close variants often return the same volume and CPC because they are grouped together, as in the example.
- **Location changes everything.** Pass a country or a city for local numbers. Without one, the figures are for the United States.
- **Paid per search.** A call is one charge plus a small amount per idea. The quote shows before the run.

## Questions

### Where does the data come from?

DataForSEO's keyword data, called through RouterGrowth.

### Is the volume monthly?

Yes, an average monthly search volume.

### Can I get keyword difficulty?

The call returns ad competition, not an organic difficulty score. Check the live results page with seo.serp to judge ranking difficulty.

### Which languages work?

Pass language with the location. Defaults follow the location.

## Related

- [Get a domain's backlinks and referring domains from one API call](https://www.routergrowth.com/tools/seo/backlink-api.md)