Keyword Research API: Get Keyword Data Without a Monthly Subscription

1. 1Need Keyword Planner volume with no monthly plan: use DataForSEO. The minimum top-up is $50, and the balance never expires.
2. 2Need Google's own volume for your own ad account: use the Google Ads API at Basic or Standard access.
3. 3Need volume history and volume by country in one SEO suite: use Ahrefs or Semrush, on a paid plan.
4. 4Need only Google Trends or autocomplete: use SerpApi. It returns no Keyword Planner volume.
5. 5Need to test before you pay: use Ahrefs free test queries or the Moz free tier.

Google sunset developer tokens on September 9, 2026. Access levels now apply to each Google Cloud project. Operations count over a sliding 24-hour window, and a call over the limit returns an error.

Explorer access blocks the planning services on production accounts. These include KeywordPlanIdeaService, KeywordPlanService and the other KeywordPlan services. Use Basic or Standard access to call them.

Standard access allows the permissible use 'researching keywords and recommendations'. Google meant that use for tools that help create and manage Google Ads campaigns.

One call returns historical metrics for up to 10,000 keywords, with up to 10 geo targets. The response includes average monthly searches, monthly volumes for up to 4 years, a competition index from 0 to 100 and a 20th percentile top-of-page bid.

GenerateKeywordHistoricalMetricsRequest request =
    GenerateKeywordHistoricalMetricsRequest.newBuilder()
        .setCustomerId(String.valueOf(customerId))
        .addAllKeywords(Arrays.asList("mars cruise", "cheap cruise", "jupiter cruise"))
        // ... geo target, language and network settings from the official sample ...

The sample sets a geo target and a language constant, and it uses the Google Search network. Set the United States as the geo target and English as the language. Then call generateKeywordHistoricalMetrics on the KeywordPlanIdeaServiceClient.

The API merges close variants. Results for car and cars come back as one result, so you can get fewer results than keywords you sent.

GenerateKeywordIdeas already returns historical metrics for each idea. Use the historical metrics call only when you already hold a keyword list. The full sample is in Google's historical metrics guide.

• Pay as you go. No subscription, a $50 minimum top-up, and a balance that never expires.
• One request costs the same for 1 keyword or 1,000 keywords. Send the full list in each request.
• Google Ads data comes from the Google Ads API, so updates follow Google, generally in the middle of the month.
• Keywords in restricted categories, such as weapons, tobacco, drugs, violence and terrorism, return no data.
• Labs clickstream data is optional. Setting include_clickstream_data=true doubles the request cost.
• DataForSEO says its route needs no developer token, approval queue or ad spend. That is the vendor's claim.

For account setup, see the OpenSEO setup guide. For every DataForSEO endpoint price, see the DataForSEO API guide.

Send up to 1,000 keywords in one array. Replace YOUR_BASE64_CREDENTIALS with your Base64 login and password.

curl --location --request POST "https://api.dataforseo.com/v3/keywords_data/google_ads/search_volume/live" --header "Authorization: Basic YOUR_BASE64_CREDENTIALS" --header "Content-Type: application/json" --data-raw '[ { "location_code": 2840, "keywords": [ "buy laptop", "cheap laptops for sale", "purchase laptop" ], "date_from": "2021-08-01", "search_partners": true } ]'

The sample response in the docs returns a cost of 0.09 and a search_volume of 2900 for 'buy laptop'.

Labs keyword ideas returns related terms for your seed keywords, with optional SERP data. It runs in live mode only.

curl --location --request POST "https://api.dataforseo.com/v3/dataforseo_labs/google/keyword_ideas/live" --header "Authorization: Basic YOUR_BASE64_CREDENTIALS" --header "Content-Type: application/json" --data-raw '[ { "keywords": [ "phone", "watch" ], "location_code": 2840, "language_code": "en", "include_serp_info": true, "limit": 3 } ]'

Labs bills $0.012 per task plus $0.00012 per item returned. Cost = $0.012 + 1,000 x $0.00012 = $0.132 for a run of 1,000 items.

Batch Keyword Overview covers up to 100 keywords at 10 units per line. Historical data costs more: in the Domain Overview example, historical data costs 50 units per line and current data costs 10.

• Lines = 2,000,000 units / 10 units per line = 200,000 Keyword Overview lines.
• Units = 5,000 keywords x 10 units per line = 50,000 units.
• Units = 50,000 Related Keywords lines x 40 units per line = 2,000,000 units.

Packages come in 2,000,000, 5,000,000, 10,000,000 and 20,000,000 units. Units renew with the plan, and unused units expire instead of rolling over.

Semrush's API access page gives no price per unit, so the cost per 1,000 keywords depends on the package you buy in your account.

The v3 keyword endpoints are deprecated for new integrations. Semrush points new work to the Keyword Reports API v4, so check the v4 unit prices in the Semrush docs before you build on it.

GET https://api.semrush.com/?type=phrase_this&key=API_KEY&phrase=seo&export_columns=Ph,Nq,Cp,Co,Nr,Td&database=us

Keyword;Search Volume;CPC;Competition;Number of Results;Trends
seo;110000;14.82;0.5;678000000;

The response is semicolon-separated text, not JSON. Set the export_columns parameter to the fields you need.

Semrush's developer docs say to upgrade to the SEO Business plan to buy API units and generate a key. Its public pricing page lists no plan by that name. It places 'Advanced API data integration' on its Advanced plan only.

Its SEO plan is listed at $139 a month, or $117.33 a month billed annually, with 5 websites and 500 tracked keywords. Confirm which plan carries the API in your account before you buy units.

The Trends API is separate. It does not use Standard API units, and its default limit is 10,000 requests a month.

• Every paid request costs at least 50 units. Units once used are non-refundable.
• Cost is the larger of 50 units and the per-row cost times the number of rows.
• A field costs 1 unit by default. Some metrics cost 5 or 10 units.
• Requests served from cache cost nothing.
• Each response reports the units used in its headers, including x-api-units-cost-total-actual.
• The default limit is 60 requests per minute. Above it, the API returns HTTP 429.

The pricing page lists credits per user, while the docs say paid plans include a monthly API unit allowance. Neither gives the API allowance for each plan.

Free test queries work on any paid plan. A request that uses only ahrefs, yep or firehose as the keyword costs no units, but you still need an API key.

GET https://api.ahrefs.com/v3/keywords-explorer/overview?country=us&keywords=ahrefs&select=keyword,volume,traffic_potential,difficulty
Authorization: Bearer YOUR_API_KEY

This is not a no-subscription route. The cheapest plan in the table above is Lite.

Moz bills rows. A keyword call bills one row for each returned value, and null values are discounted. Fetching search intent raises the quota cost.

• Moz Pro does not include paid API access. The API is a separate product.
• Every plan includes keyword metrics, keyword suggestions, search intent and ranking keywords calls.
• Search intent is opt-in through options.include_intent, which defaults to false.
• Keyword data comes from Moz's own index, so treat its volume as Moz's own estimate, not Google's.

The keyword metrics method is data.keyword.metrics.fetch. It returns difficulty, volume, organic CTR, priority and search intent. A separate volume method and a keyword suggestion list method also exist.

Read the parameters for the keyword method on its method page, where they sit in a collapsed section.

curl -X POST https://api.moz.com/jsonrpc -H "x-moz-token: <YOUR_MOZ_TOKEN>" -H "Content-Type: application/json" -d '{ "jsonrpc": "2.0", "id": "99edd07d-fd2e-4a9c-834f-64a6629452cf", "method": "quota.lookup", "params": { "data": { "path": "api.limits.data.rows" } } }'

The quota lookup checks your row quota. The API is JSON-RPC, sent as POST to https://api.moz.com/jsonrpc with the x-moz-token header.

Only successful searches count. Cached, errored and failed searches do not.

Cost = $25 / 1,000 searches = $0.025 per search. That is a price per search, not a price per keyword of volume.

SerpApi offers no Keyword Planner search-volume endpoint. Use it for Google Trends and Google Autocomplete.

GET https://serpapi.com/search?engine=google_trends&q=coffee,milk,bread,pasta,steak&data_type=TIMESERIES&api_key=YOUR_KEY

Interest over time and compared breakdown by region take several queries per search. Other Trends data types take a single query. Autocomplete uses engine=google_autocomplete with q as the query.

Among the subscription plans, Platinum has the lowest cost per credit ($0.18), but it is the largest annual commitment. The $8,000 pack is cheaper still at $0.16, and pack credits expire after one year.

• One credit covers one keyword result, and the API takes up to 100 keywords per request.
• A credit is spent even when the keyword has no search volume.
• The dataSource value gkp returns Google Keyword Planner data only. The value cli adds Clickstream data.
• All API methods are open on every plan, including Bronze.
• An invalid subscription or too few credits returns HTTP 402.

POST https://api.keywordseverywhere.com/v1/get_keyword_data
Authorization: Bearer YOUR_API_KEY
Accept: application/json
Content-type: application/json

{"kw":["keywords tool","keyword planner"],"country":"us","currency":"usd","dataSource":"cli"}

The response includes vol, cpc, competition, a 12-month trend array, credits left and credits_consumed. Get Credit Balance is GET /account/credits.

The Bing Webmaster API needs a Bing Webmaster Tools account. Use OAuth 2.0, which Microsoft recommends, or an API key. Each user can generate one API key.

Two methods return keyword data. GetKeywordStats returns historical statistics for a query. GetKeyword returns impressions for a chosen period.

GetKeywordStats(System::String ^ q, System::String ^ country, System::String ^ language)
GetKeyword(System::String ^ q, System::String ^ country, System::String ^ language, DateTime startDate, DateTime endDate)

Microsoft labels these reference pages as prerelease, so they may change. The pages give no price, quota or definition of the volume figure.

Bing data covers searches on Bing only, so expect it to differ from Google volume.

Google announced the Trends API in alpha on July 24, 2025. Access is by application only, for a limited set of developers.

The API returns consistently scaled data, not a 0 to 100 score per request. You can merge requests and compare dozens of terms, while the Trends website compares eight.

The website scales each term from 0 to 100 against its share of all searches. The result is search interest, not search volume. Trends uses a sample of searches, not the full set.

The Trends API alpha is open by application only, so there is no public request example. For a working Trends call, use the SerpApi Trends endpoint shown in the SerpApi section.

Google calls its volumes approximate. The average monthly searches field is an approximate average over 12 months, and the monthly search volumes field holds approximate counts for each month.

Google describes Keyword Planner volumes as estimates, not counts. Close variants merge into one result, so the volume for car can include cars.

Keyword Planner competition is the number of ad slots filled divided by the slots available, scaled from 0 to 100. It measures advertiser demand, not how hard it is to rank in organic results.

For ranking difficulty, use a metric built for SEO. Moz's keyword metrics call returns a difficulty field.

A 2016 Search Engine Land report said advertisers with little or no spend see volume in ranges in the Keyword Planner interface. The report covers the interface, not the API, and it is ten years old.

Google said most advertisers see Keyword Planner data as usual, while advertisers with a lower monthly spend could see limited data.

DataForSEO says the Keyword Planner interface shows ranges unless you spend on ads, and that its API returns exact values. Treat the second part as the vendor's claim.

Keyword Planner data covers Google Search only and refreshes monthly. Keywords Everywhere can return Keyword Planner data alone or with Clickstream data. Moz uses its own index. Trends returns a relative interest score.

Pick one source per project and compare keywords only inside it. For the wider process of keyword research, see SEO fundamentals.