The lowest cost SEO API is the one that’s cheapest for the jobs you actually run, and that’s rarely the one with the lowest plan price. Compare four things: what the plan with API or MCP access costs, what one call costs in dollars, whether credits are per user or per account, and what happens to the credits you don’t use. On those terms, The SEO MCP is free to start with 1,000 credits once you verify your email, then $99/mo for 50,000 credits shared across 93 tools. Ahrefs lists API and MCP access from its $129/mo Lite plan, with 1,000 credits per user.
Last updated: November 2026
Everyone compares plan prices. Few compare the price of a call
Ask anyone what an SEO API costs and you’ll get a monthly figure. It’s the number on every pricing page, so it’s the number everyone remembers.
But you don’t buy a month. You buy answers: a search volume lookup, a page of Google results, a list of a competitor’s keywords. Two APIs at the same monthly price can differ a lot in what each of those answers costs, and the gap usually hides in three places: the unit, the rounding and the tier.
Here’s how each one works, using our own pricing as the worked example, since it’s the one I can show you down to the call.
Where each vendor lists API or MCP access
Start with the plan that actually includes programmatic access, not the cheapest plan on the page.
| Vendor | Where API or MCP access is listed | That plan’s price | How usage is counted |
|---|---|---|---|
| Ahrefs | Lite and up | $129/mo (Lite) | 1,000 credits per user on Lite; unlimited credits from Standard ($249/mo) |
| Semrush | Semrush One Starter and Pro+; SEO Classic Pro and Guru | $199/mo (One Starter), $299/mo (Pro+) | 50,000 API units a month for MCP |
| Local Falcon | Has its own MCP server | Plans from $24.99 to $199.99/mo | Credit-based, built for local rank tracking |
| The SEO MCP | Every plan, including Free | $0, then $99/mo | 50,000 credits a month on the $99 plan, one balance per account |
Competitor figures come from each vendor’s published plans; check theirs before you buy, because plans change. Ours are on the pricing page.
The unit: credits don’t convert between vendors
Fifty thousand Semrush API units and fifty thousand SEO MCP credits look like the same allowance. They aren’t. Each vendor decides what one unit buys, so the raw numbers can’t be compared.
The only fair test is to price one real job on each. Pick something you do every month, like pulling volumes for your keyword list, and work out what that job costs on each plan, in dollars.
Dollars per call, at our Growth Engine rates
Our tools page lists every tool’s credit cost at Growth Engine rates. That plan is $199 for 200,000 credits, so one credit is about a tenth of a cent. That turns credit costs into prices you can reason about:
| Job | Credits | About |
|---|---|---|
| One page of live Google results | 8 | 0.8 cents |
| Search volume for up to 1,000 keywords | 130 | 13 cents |
| Keywords a domain ranks for, per started 100 results | 35 | 3.5 cents |
| A 5x5 Google Maps geo-grid scan | 300 | 30 cents |
Now the tier part, which most people don’t realize. Higher tiers use more credits per call, but each credit costs less. Local Dominator charges fewer credits per call than the figures above, Full Stack charges more, and a Full Stack credit costs less than half as much as a Growth Engine one. In dollars, our tools page says calls are cheapest on Full Stack. That’s why comparing tiers by credit count alone gets the answer backwards.
The rounding that quietly doubles a bill
Two pricing rules matter more than the headline rate.
Started blocks of 100. Bulk tools charge once for each started block of 100 results, keywords or domains. Ask for 120 competitor keywords and you pay for two blocks (70 credits). Ask for 100 and you pay for one (35). Round your requests down to the hundred.
One call versus many. The search volume tool costs 130 credits a call and takes up to 1,000 keywords. Send 1,000 keywords in one call and it’s 130 credits. Let your assistant send them in ten batches of 100 and it’s 1,300. Tell it to use one call.
My own view is that this matters more than which vendor you pick. A sloppy prompt habit can cost more each month than the difference between two plans.
When $99 isn’t low cost
I’ll be straight about where our pricing works against you. Paid plans are monthly subscriptions. Credits reset on your billing date and don’t roll over, and there are no SEO credit top-ups: if you run out, you upgrade, and the new plan’s credits are added straight away.
So if your real usage is a few thousand credits a month, $99 buys mostly unused credits. In that case, Google’s free tools plus one single-purpose tool may be cheaper, and our cheap SEO tools post walks through that by job. The SEO MCP is cheap per job when one balance replaces two or three separate subscriptions, or when you use it most days.
Our answer to “is it worth it?” starts with the free 1,000 credits. Run a normal week of your own questions, note what they cost, then multiply. Connecting takes one hosted URL and a browser sign-in (our Claude MCP SEO post covers Claude). If you’ve never used an API before, read SEO API without coding first. For a page-level example of what a call returns, see the AI SEO audit tool post, and for the wider field, our AI SEO tools guide.
Frequently asked questions
What is the cheapest SEO API?
It depends on the jobs you run. Price one real monthly job on each option, in dollars. Ahrefs lists API and MCP access from its $129/mo Lite plan, and Semrush lists MCP on Semrush One Starter ($199/mo) and Pro+ ($299/mo), among others. The SEO MCP starts free with 1,000 credits once you verify your email, then $99/mo for 50,000 credits across 93 tools.
How much does one call cost on The SEO MCP?
At Growth Engine rates ($199 for 200,000 credits), a live Google results page is 8 credits, about 0.8 cents. A search volume call is 130 credits for up to 1,000 keywords, about 13 cents. Bulk tools charge per started block of 100 results. Local Dominator uses fewer credits per call and Full Stack more, so ask your assistant to read the server’s pricing resource for your plan.
Are Semrush API units the same as SEO MCP credits?
No. Each vendor defines its own unit, so 50,000 Semrush API units and 50,000 SEO MCP credits don’t buy the same amount of data. Ahrefs counts usage in its own credits too, with 1,000 per user on Lite. Compare vendors by pricing a job you actually run on each, such as a monthly keyword volume pull, rather than by unit totals.
Which SEO MCP plan has the cheapest cost per call?
Full Stack, in dollars. Higher tiers use more credits per call, but a Full Stack credit costs less than half as much as a Growth Engine credit, so each call costs less overall. That only pays off if you use the volume: Full Stack is $399 a month for 1,000,000 credits, and unused credits don’t roll over.