Semrush API pricing in 2026: Ahrefs and SerpApi compared, and cheaper options

The Semrush API costs at least $499.95 a month before your first request. The Standard API is an add-on to the SEO Toolkit Business plan, your API unit balance starts at zero, and you then buy a package of 2, 5, 10 or 20 million units, priced inside your account rather than on Semrush's public pages. The Ahrefs API is cheaper to reach: every paid plan from Lite at $129 a month includes API units (200,000 a month on Lite). SerpApi starts free with 250 searches a month, then $25 a month for 1,000. If you only need keyword volumes or Google positions, a pay-per-call API costs less: Cite42 charges $0.09 for monthly search volume, CPC and competition on up to 50 keywords, and $0.09 per keyword to find where a site ranks in Google's top 100, with no subscription.

Cite42 publishes this guide and is one of the options in it. We read each vendor's official pricing and documentation pages on October 23, 2026, and did not buy their plans or make paid test calls.

Semrush, Ahrefs and SerpApi API pricing at a glance

Semrush API pricing: the Business plan plus API units

Semrush's Standard API, which bundles the Analytics (SEO) API and the Projects API, is an add-on to the Business tier of the SEO Toolkit. Semrush's SEO Toolkit pricing page lists Business at $499.95 a month. Pro ($139.95) and Guru ($249.95) don't include the Standard API.

Upgrading to Business gives you no units. Semrush's API access guide says the balance "will still be zero" after the upgrade, so you buy a package of 2, 5, 10 or 20 million units under Subscription info and then create an API key. Purchased units renew with the subscription, and unused units expire instead of rolling over. Neither the knowledge base nor the developer docs publish the package prices; Semrush shows them when you buy and quotes custom volumes through sales.

You spend units per line of each report, so the bill depends on what you pull:

• Domain Organic Search Keywords costs 10 units per line for live data and 50 per line for historical data. Semrush's own example: 1,000 keywords for each of 100 domains uses 1,000,000 units live or 5,000,000 historical.
• The backlinks example in the knowledge base costs 40 units per line.
• In the Projects API, adding a keyword to a Position Tracking campaign costs 100 units, and creating a campaign costs another 100.

Two terms matter if you're building a product on it: no more than 10 requests per second, and no caching of Semrush data for more than a month without written consent.

Pros

• Keyword data in more than 140 country databases, with keyword difficulty, backlinks and traffic data in the same account.
• Position Tracking and Site Audit campaigns can be created and read through the Projects API.

Cons

• About $500 a month before the first unit, and package prices you only see inside your account.
• Per-line unit costs make the monthly bill hard to predict until you've run your real queries.

Semrush MCP: 50,000 units on lower plans

The Semrush MCP server at https://mcp.semrush.com/v2/mcp is the cheaper way to get Semrush data into Claude, ChatGPT or Cursor. Semrush One Starter, Semrush One Pro+ and the SEO Toolkit (SEO Classic) Pro and Guru plans include 50,000 API units for it, refreshed on your renewal date. Semrush One Advanced and SEO Toolkit Business work too once you add a unit package. The server spends units the same way the REST API does.

Semrush's pricing page lists Semrush One Starter at $199 a month ($165.17 a month billed annually), Pro+ at $299 and Advanced at $549. Fifty thousand units covers small lookups, but it goes quickly on reports that cost 10 to 50 units per line.

Ahrefs API pricing: units included from Lite

Ahrefs includes API and MCP access on its paid plans. Its pricing explainer (March 2026) and pricing page give these monthly allowances:

Each request costs at least 50 units. Most fields cost 1 unit per returned row and some metrics cost 5 or 10, so a request costs whichever is greater: 50 units or its row cost (limits and consumption). Free test queries against set targets show what a request will cost before you spend units on it, and the Ahrefs MCP server draws from the same allowance. The API covers keywords, backlinks, rank tracking, site audits and brand visibility in AI answers.

Pros

• API access on the $129 plan, without buying units separately.
• Backlink and keyword data from the same index as the Ahrefs web app.

Cons

• The 50-unit floor per request makes many small lookups expensive.
• The subscription comes first, and Enterprise needs an annual commitment.

SerpApi pricing: monthly search plans

SerpApi sells monthly search allowances, month to month, and you can cancel anytime. Cached searches are free. The plans on October 23, 2026:

SerpApi returns search results pages as JSON. It doesn't return search volume, CPC or backlinks. For rank tracking, count pages rather than keywords: Google stopped showing up to 100 results per page in 2025, so finding a site at position 73 can take up to 10 paginated searches for one keyword.

Pros

• A free plan to build against, and many search engines beyond Google.
• Plain monthly plans with no unit math.

Cons

• Results pages only, with no keyword volumes.
• Deep rank checks multiply your search count.

Cheaper ways to get keyword data and rankings

Most people pricing the Semrush API need one slice of it: monthly search volume for a list of keywords, or where their site ranks for a set of keywords. Several APIs sell that slice without a suite plan.

Cite42: keyword volume and Google positions per call

Cite42 is a pay-per-call API and MCP server for keyword data, Google rankings and AI visibility. There is no subscription. You pay only for successful calls from a prepaid balance that never expires, the minimum top-up is $25.00, and a verified signup adds $1.00 of free credit.

• Keyword Research returns monthly search volume, CPC and paid-search competition in 13 countries. A batch of 2 to 50 keywords costs $0.09, or $0.03 if none of them has volume. A single keyword costs $0.03 to $0.12 depending on the result, and the top price includes up to 50 related keyword ideas.
• Keyword Rankings checks where your domain ranks in Google's top 100 for 1 to 5 keywords per call, in 40 countries, on desktop or mobile. It costs $0.09 per keyword checked, and a keyword whose results could not be fetched is free. Each result includes the ranking URL, your other URLs in the top 100, up to five competitors' positions, the top 10 results and whether the Google AI Overview cites your site.

Keyword Research works over REST and MCP today. Keyword Rankings runs on the REST API and in the dashboard, and its MCP tool follows. Neither gives you keyword difficulty, backlinks or site audits, and that's where Semrush and Ahrefs still earn their price.

DataForSEO, SE Ranking and Serper

• DataForSEO is pay-as-you-go with a $50 minimum top-up, and funds don't expire. A Google Ads search volume task takes up to 1,000 keywords for $0.06 in the standard queue or $0.09 live. A Google organic results page costs $0.0006 per 10 results queued or $0.002 live, so a top-100 check is $0.006 or $0.02, and you parse the raw results yourself.
• SE Ranking sells API credits pay-as-you-go from a $50 deposit, with 100,000 free trial credits, and covers keywords with difficulty, backlinks, audits, rank tracking and AI visibility.
• Serper.dev gives 2,500 free Google queries, then $50 for 50,000 credits that stay valid for six months.

The DataForSEO alternatives guide and the keyword research API comparison cover these in more depth, and the best SEO APIs by job adds backlink and audit APIs.

What one small project costs on each API

Take a typical small-site job: monthly volume for 50 keywords once, then a weekly check of where the site ranks for 25 of them (top 100, US, desktop). That's about 108 keyword checks a month.

DataForSEO is the cheapest per check if you're willing to store and parse raw results pages yourself. Cite42 costs more per keyword but returns the position, ranking page, competitors and AI Overview citation ready to use, and its tracker checks a move of 10 or more places a second time before reporting it. Semrush and Ahrefs make sense once you also need difficulty, backlinks and audits from one vendor.

When Semrush or Ahrefs is still worth it

• You need keyword difficulty, search intent, backlinks and competitor traffic for the same keywords.
• Your team wants a web app as well as the API.
• You pull large historical reports, where per-line units can work out cheaper than per-call prices.

Frequently asked questions

How much does the Semrush API cost?

The Semrush Standard API needs the SEO Toolkit Business plan at $499.95 a month, and the unit balance starts at zero, so you also buy a package of 2 to 20 million API units. Semrush shows the package prices in your account rather than on its public pages (as of October 23, 2026). The Semrush MCP server is cheaper to reach: Semrush One Starter, at $199 a month, includes 50,000 units for it.

Is the Semrush API included in the Pro or Guru plan?

No. Pro and Guru don't include the Standard REST API, which needs Business. They do include 50,000 API units for the Semrush MCP server, as Semrush One Starter and Pro+ do.

How much does the Ahrefs API cost?

The Ahrefs API comes with its paid plans. Lite at $129 a month includes 200,000 API units, Standard at $249 includes 800,000 and Advanced at $449 includes 2,000,000, and each request costs at least 50 units.

How much does SerpApi cost?

SerpApi has a free plan with 250 searches a month. Paid plans start with Starter at $25 a month for 1,000 searches, then Developer at $75 for 5,000 and Production at $150 for 15,000, all month to month.

Is there a cheaper alternative to the Semrush API for keyword data?

Yes. Cite42 returns monthly search volume, CPC and competition for up to 50 keywords for $0.09 per call, with no subscription, a $25.00 minimum top-up and a balance that never expires. DataForSEO charges $0.06 to $0.09 for up to 1,000 keywords after a $50 minimum top-up, and SE Ranking sells pay-as-you-go credits from a $50 deposit.

Price your own workload

List the reports you would actually call each month, then price that list on two of the APIs above. To try Cite42, create a free account for $1.00 of credit, get a key from the dashboard and follow the API documentation, or see every price on the pricing page.