Keyword Tool API vs SEO API (2026): which should you pick?
As of Nov 13, 2026, SEO API grades higher than Keyword Tool API: 2.4 against 1.8 out of 4.0.
Checked Oct 23, 2026 and Nov 13, 2026 · graded Oct 23, 2026 and Nov 13, 2026 by ToolGPA
Keyword Tool API grades higher on features and platforms. SEO API grades higher on value for money and the free plan. They get the same grade on ease of use.
Price, platforms and features side by side. The table says where each price was read and when.
Keyword Tool API
Keyword suggestion and search volume API across 17 search platforms
Which one is for you
Pick Keyword Tool API if
- Fits if you want Google and Bing search volumes pulled into your own tools or warehouse
- Works for long-tail research on YouTube, Amazon and TikTok as well as Google
Look elsewhere if
- Not for you if you want to try it first, as there's no trial, only a 30-day money-back guarantee
- Tight if you run many jobs, since Starter's 50 requests a day are shared with the web app and MCP
- Watch out: volumes for platforms other than Google and Bing are modeled estimates, not planner data
- Pricey if you pay monthly, at $88 against $68 on yearly billing
Pick SEO API if
- Fits if you need to check whether a visitor really is Googlebot or an AI crawler
- Works for technical SEOs who want a quick URL parser or HTTP status checker
Look elsewhere if
- Not for you if you want rankings, keywords or SERP data: it does not provide them
- Watch out: no rate limits, uptime commitment or terms were stated on the pages we read
- Skip it if you need a company behind it: it is run by an individual consultant
- Too light for a team that needs support, as no support channel is listed
How we grade them
| 1.8GPAKeyword Tool APIWeak | 2.4GPASEO APIFair | |
|---|---|---|
| Value for money | CStarter is $68 a month on yearly billing ($88 monthly) for 50 requests a day, above this category's dearer quarter but short of its dearest tenth. The same plan also covers the web app and MCP. | BEverything listed is free of charge, which beats the $11.40 mark for data APIs. But the lists are small reference data rather than a data service, so we stop at a B. |
| Free plan and trial | FNothing free for the API: no trial, only a 30-day money-back guarantee, which isn't a trial. A free Guest MCP gives suggestions with volume on the first 5 keywords, but no API access. | AAll listed APIs and tools are free outright, with no plan or trial to run out. |
| Features | CSearch volume for up to 1,000 keywords a request, suggestions from 17 platforms, competitor keywords and a sandbox. The listing's own gap: only Google and Bing volumes come from the ad planners, and the rest are modeled estimates. | DBot IP lists, a URL parse API and a handful of tools such as an HTTP status tester. It does one narrow job and does not give keywords, rankings or search results. |
| Ease of use | CJudged on how fast a developer gets a first result: a sandbox base URL and a public OpenAPI 3.1 file for Postman or generated clients. No rating on record, and one daily request pool is shared with the web app and MCP. | CNo store rating on record. Lists are easy to read, but using them as an API means calling them from your own code. |
| Platforms and integrations | BWeb, with an API, an MCP server for Claude, ChatGPT and Cursor, and an OpenAPI file for Postman. No desktop or phone app, so B is the top. | CWeb pages and simple APIs only, with no integrations listed. |
| Best for | keyword volumes from Google, YouTube and Amazon | free lists of search and AI crawler IPs |
The GPA is the average of the five grades: an A is 4 points, an F is none. The full reasons are on each tool's page: Keyword Tool API and SEO API. How we grade
Price against what you get
Keyword Tool API starts at $68 a month and scores 2.3 out of 4 on features, ease of use and platforms. SEO API has no paid plan and scores 1.7.
Keyword Tool API scores higher, and starts $68 a month higher: the question is whether the extra is worth that to you. Of the other SERP and SEO data APIs on the chart, 11 score higher than Keyword Tool API for less, and none scores higher than SEO API for less.
Features, ease of use and platforms, averaged
What paid plans start at, a month (each step along is roughly double) →
- The best score at each price
- Has a free plan
- No free plan
Where they differ
- Keyword Tool API also covers keyword research.
- SEO API also covers page speed.
At a glance
| Keyword Tool API | SEO API | |
|---|---|---|
| Pricing | Paid | Free |
| Starts at | $68 per month for 50 requests a day, billed annually ($88 billed monthly) | Free |
| Free plan | None | The site describes its SEO APIs as free of charge. |
| Free trial | None listed | None listed |
| Web | ||
| Made by | Essential Apps LLC and Key Tools Limited | Fili, technical SEO consultant |
| Price read from | keywordtool.io | seoapi.com |
| Checked | Oct 23, 2026 | Nov 13, 2026 |
Worth knowing
Keyword Tool API
- The API needs a Keyword Tool Pro plan; there is no free trial, but every plan has a 30-day money-back guarantee.
- One daily request pool, from 50 on Starter to 400 on Agency, is shared by the web app, the API and MCP, and resets every 24 hours.
- Only Google and Bing volumes come from the ad planners; the other platforms' volumes are modeled estimates from clickstream data.
- A free Guest MCP gives Google and Bing suggestions with volume on the first 5 keywords, but no API access.
SEO API
- It is a set of free reference lists and small tools, not a keyword, ranking or SERP data service.
- The pages read do not state rate limits, an uptime commitment or terms of use.
- It is run by an individual technical SEO consultant, not a company with a pricing page.
Key features
Keyword Tool API
- Search volume endpoint
- Send 1 to 1,000 keywords per request for monthly volume, a monthly breakdown, cost per click and competition, for one location and language.
- Keyword suggestions from 17 sources
- Autocomplete suggestions, related keywords, questions and prepositions from Google, YouTube, Bing, Copilot, Perplexity, Amazon, TikTok, Reddit and more.
- Competitor keywords
- Pass one URL to get up to 2,000+ keywords Google associates with it, with volume, cost per click and low and high top-of-page bids.
- Deep localization
- Google data for 190+ countries, 68,000+ locations and 50+ languages; Bing planner data for 6 countries, or device data for 32.
- Sandbox and OpenAPI spec
- A sandbox base URL for testing without using quota, and a public OpenAPI 3.1 file for Postman collections or generated clients.
- MCP server
- Connect Claude, Cursor or ChatGPT to the same data through MCP, drawing on the plan's shared daily request pool.
SEO API
- Search engine bot IPs
- Address lists for Googlebot, Bingbot, YandexBot, Applebot, Baiduspider, DuckDuckBot and other search crawlers.
- AI bot IPs
- Address lists for OpenAI GPTBot, Anthropic ClaudeBot, PerplexityBot, Amazonbot, Meta-ExternalAgent and CommonCrawl CCBot.
- URL Parse API
- A listed API marked new on the site; the pages read do not describe its output.
- SEO toolbox
- An HTTP Status Tester, a Cumulative Layout Shift debugger and a disavow file validator.
Plans
Keyword Tool API
Starter$68
per month for 50 requests a day, billed annually ($88 monthly)
Search volume for up to 50,000 keywords a day, 12 months of history, all 17 platforms, web app, API and MCP.
Growth$148
per month for 100 requests a day, billed annually ($188 monthly)
Search volume for up to 100,000 keywords a day and 24 months of history.
Scale$308
per month for 200 requests a day, billed annually ($388 monthly)
Search volume for up to 200,000 keywords a day and 48 months of history.
Agency$628
per month for 400 requests a day, billed annually ($788 monthly)
Search volume for up to 400,000 keywords a day and 48 months of history.
Enterprise & CustomCustom
Higher daily request and keyword limits, custom API and MCP usage, procurement paperwork and bank-transfer payment, after a demo.
SEO API
Free$0
All listed APIs and tools are offered free of charge.
Ways to pay less
Keyword Tool API
- Annual discount
Save over 20% with annual billing
Keyword Tool's pricing lists annual billing at over 20% less: Starter is $68 a month billed annually instead of $88 billed monthly.
SEO API
No public discounts listed.
Common questions
Which is cheaper, Keyword Tool API or SEO API?
As of Nov 13, 2026, SEO API is cheaper to start with: it is free, against $68 a month for Keyword Tool API. Keyword Tool API starts at $68 per month for 50 requests a day, billed annually ($88 billed monthly), and SEO API is free.
Which has a free plan, Keyword Tool API or SEO API?
As of Nov 13, 2026, only SEO API has a free plan. Keyword Tool API does not.
More comparisons
How this page was made
- The verdict at the top follows a fixed rule. When both tools are in the same category and either is in our top three for it, the verdict follows that ranking: the higher-placed tool is our pick. The top three weigh who each tool suits as well as its grades, so a pick can go against the GPA. Otherwise the page does not pick one and says which grades higher: the higher GPA first; on a tie, the one with a free plan, then the one that starts cheaper in dollars a month, counted the same way for both; if they are still level, what the choice depends on.
- The grades are our own, from each tool’s review or report card. The GPA is their average.
- Prices, plans and platforms come from each tool’s listing. The table above says where each price was read and when.
- The differences and the answers to the questions are worked out from those listings.