Every Japanese shop's price for a product, with two years of daily price history
Kakaku.com (価格.com) is Japan's largest price-comparison site: for each product it lists the shops selling it, cheapest first, and keeps a daily price history.
6 active endpoints, on 2 and 3 credit tiers.
- POST/kakaku/v1/search
- POST/kakaku/v1/product
- POST/kakaku/v1/offers
- POST/kakaku/v1/specs
- POST/kakaku/v1/price_history
- POST/kakaku/v1/ranking
What Kakaku.com endpoints does ReefAPI ship?
6 live read endpoints. Read-only data API: no writes, no account actions, no dashboard access on the target site.
Kakaku.com API
5 of 6 endpoints, ready to run
Find products by keyword, in Japanese or English
// Press "Try it" and this pane shows exactly what the // live site returned this second — including an empty // result, if that is the truth. No key, no account.
How the Kakaku.com API works
Kakaku.com is a normal ReefAPI surface — the same four rules that hold for every other engine on the key.
No OAuth app, no request signing, no per-site account. One key covers all 491 engines.
Every route is a POST with a JSON body. Parameters are validated against the published schema before anything is charged.
Credits, not seats. Failed and blocked calls are never charged, and cache hits cost nothing.
One envelope everywhere. meta carries latency_ms, record_count and the endpoint that answered.
From a keyword to every shop's price and its history
Search, pick the catalogue products, then read their shop tables and price history.
Rows with row_type product carry a product_id; mall listings and smartphone model pages are marked, sponsored rows come back in sponsored[].
Every shop with price, gap to the cheapest, shipping as printed, points, stock text and the shop's rating share.
Daily lowest and average price, up to 731 days, plus the lowest price in that window and its date.
The product's category ranking, with the key product returns.
A dated Japanese price feed: the cheapest shop, every competing shop and the two-year price curve for each product you track.
curl -X POST https://api.reefapi.com/kakaku/v1/search \
-H "x-api-key: $REEF_KEY" \
-H "content-type: application/json" \
-d '{"query":"SSD 2TB"}'{
"ok": true,
"data": { … },
"meta": {
"api": "kakaku",
"endpoint": "search",
"mode": "live",
"latency_ms": …,
"record_count": …
},
"error": null
}What a Kakaku.com field actually contains
Fields that read differently from how they look. Every row was measured against live Kakaku.com pages on 2026-10-14.
| Field | What it holds |
|---|---|
| product_id | Kakaku's product number, K followed by 10 digits (K0001719316), as in kakaku.com/item/K…/. Pass it unchanged to product, offers, specs and price_history; a product URL works too. Search to product returned the same id and title on 9 of 9 products. |
| row_type | search mixes four kinds of rows: product (a kakaku catalogue product with a product_id), phone_model (a smartphone model page, priced as the handset), mall_item (a Rakuten, Amazon.co.jp or Yahoo! Shopping listing kakaku indexes) and sponsored rows, which are returned in sponsored[] and never in results. The price sorts and the mall filter answer with mall listings. |
| price_from (search) | The from-price printed on the search card. It comes from kakaku's search index and can lag the product page: 1 of 9 cards differed on 2026-10-14 (52,455 on the card, 52,344 on the product page). For the live price use product or offers. |
| lowest_price, average_price | lowest_price is the cheapest shop price on the product page; it matched the page's structured data and the first shop row on 9 of 9 products. average_price is kakaku's average across shops, not a price anyone sells at. Both are yen including consumption tax. |
| shipping_text, shipping_cost | Kakaku sets shipping per prefecture. shipping_text is what the table prints: 無料 (free), 無料～ (free to some prefectures, more to others) or an amount. shipping_cost is set only when the text is one exact amount; effective_price (price + shipping - points) only then too. |
| points | The point reward the shop prints next to its price, in yen (550円相当 = 550). |
| shop.rating_pct, shop.rating_count | The share of buyers who rated the shop positively over the last six months and how many ratings that is, as kakaku's shop page prints it (98 % of 351). It is not a 5-star score; null when the shop has no rating yet. |
| sales_rank.category | The key of the product's own category ranking (game/game-console/ranking_2050). Pass it to ranking unchanged: the product sat at the same rank in that ranking on 4 of 4 checks. |
Kakaku shows the same shops, prices and shipping text to every visitor: one product read from three different countries in the same minute returned identical offers. Prices are in yen including Japanese consumption tax.
Kakaku.com coverage, measured
Every number below was read from live Kakaku.com responses on 2026-10-14, in two consecutive runs of 74 calls each, 148 of 148 answered as expected.
Japan, prices in yen including consumption tax. "iphone" matched 11,281,255 results, "ノートパソコン" 916,803, "SSD 2TB" 20,444 (catalogue products and indexed mall listings together).
"SSD 2TB" 20,444 → category パソコン 20,254, Rakuten 3,722, Amazon.co.jp 11,172, 10,000 to 20,000 yen 143 (40 of 40 rows in range), from 50,000 yen 14,517 (40 of 40 in range).
Lowest price matched the page's structured data, the first shop row and that day's price-history point on 9 of 9 products; every shop's gap to the cheapest added up on 143 of 143 rows.
From 1 (maker-direct models) to 50 shops measured; all shops come in one call.
Search to product returned the same id and title on 9 of 9 products; product's ranking key led to the same rank on 4 of 4 categories.
Search card prices come from kakaku's index and can lag the product page; shipping varies by prefecture and is returned as printed; review texts, Q&A threads and smartphone carrier plans are not returned.
What people build with Kakaku.com
The jobs this data is most often used for.
endpoints
credits per call
Monitor the cheapest Japanese shop price and the number of shops for a list of products every day.
Build a price-history dataset from two years of daily lowest and average prices per product.
Compare shop prices, shipping and point rewards for one product across all Japanese shops.
Track category sales rankings (SSD, game consoles, cameras, notebooks) and rank movement.
What Kakaku.com data costs
The cheapest call here is 2 credits, so $15/mo (Pro) buys 5,000 of them — $1.50 per 1,000 credits. Credits roll over and never expire, and failed or blocked calls are not charged.
Full pricing →- 1,000 free credits on signup, no card
- One key, all 491 APIs, one credit pool
- Failed and blocked calls are never charged
- Credits roll over and never expire
Call it in two lines
Sign up, get 1,000 credits and one key that works on every engine. Then this is the whole protocol.
curl -X POST https://api.reefapi.com/kakaku/v1/search \
-H "x-api-key: $REEF_KEY" \
-H "content-type: application/json" \
-d '{"query":"SSD 2TB"}'import requests
r = requests.post(
"https://api.reefapi.com/kakaku/v1/search",
headers={"x-api-key": REEF_KEY},
json={
"query": "SSD 2TB"
},
)
print(r.json()["data"])Have a question? We got answers.
The questions people actually ask before wiring up Kakaku.com.
Get a free key →Do I need a Kakaku.com account?▾
No. Everything is read logged out, and you call reefapi.com from anywhere.
Can I search in Japanese?▾
Yes. Japanese and English words both work, and full-width letters are normalised: "ｉｐｈｏｎｅ" and "iphone" returned the same 11,281,255 results on 2026-10-14.
How many shops does offers return?▾
All of them, in one call. The most measured on 2026-10-14 was 50 shops for one camera; a product sold only on its maker's own site has one row and product says maker_direct_only.
Which search filters are there?▾
Category, mall, price range and price sort. Each was checked against the unfiltered count in the same run: "SSD 2TB" 20,444 → category パソコン 20,254, Rakuten 3,722, Amazon.co.jp 11,172, 10,000 to 20,000 yen 143, from 50,000 yen 14,517.
How far back does price_history go?▾
Up to two years of daily points (731 days measured). Days before kakaku listed the product are left out, so a product launched in February starts in February.
Does the price depend on where I call from?▾
No. The same product read from three countries in the same minute returned the same shops, prices and shipping text.
Do you return the review texts?▾
Not yet. product returns the review score and the number of reviews and Q&A threads; the review texts themselves are not returned.
How deep does ranking go?▾
As deep as kakaku ranks the category, 40 per page: the SSD ranking had 77 products on 2026-10-14 (page 2 = 41 to 77). A page past the end answers NOT_FOUND.
What is the Kakaku.com API?▾
Kakaku.com API is a ReefAPI endpoint group for japan's largest price comparison: every shop's price for a product, daily price history, specs and category sales rankings. It returns live JSON through POST requests under /kakaku/v1.
Is the Kakaku.com API free to try?▾
Yes. ReefAPI starts with 1,000 free credits, no card required. Kakaku.com calls use the same shared credit balance as every other ReefAPI engine.
Do I need a Kakaku.com login or account?▾
No login to Kakaku.com is needed for the API response. You call ReefAPI with your x-api-key header, and the playground can run live examples before you create a production key.
How fresh is the Kakaku.com data?▾
The page example is captured from a live search call, and production requests fetch live data through ReefAPI rather than a static sample.
How many credits does the Kakaku.com API use?▾
Kakaku.com actions currently cost 2-3 credits per successful call. Failed or blocked calls are free. All APIs draw from one credit pool.
Can I call Kakaku.com from an AI assistant or MCP client?▾
Yes. Connect ReefAPI once through MCP and your assistant can call kakaku actions with the same key, credit pool and JSON envelope used by normal REST requests.
231 E-commerce & Marketplaces APIs on the same key
One key, one credit pool, one response envelope. If you are pulling Kakaku.com, you are one call away from the rest of the category — no second contract, no second integration.
Need something this API does not do?
Name the endpoint, the field, or a source we do not carry yet. We ship new APIs every week and you would be first to get the key. Real people read every message and reply the same day.
Try it on your own data before you pay anything
The call above is the real endpoint, not a recording. A free key gives you 1,000 credits, the other 490 APIs, and the same envelope everywhere.
Endpoints, parameters and credit costs on this page are read from the live catalog and cannot drift from what the API accepts. Field notes were captured on 2026-10-14.