What Is J-Quants? Research Uses and Limits
J-Quants provides Japanese market data for individual users.
Start with a research question
J-Quants provides Japanese market data for individual users. Access to observations is the beginning of research, rather than evidence that a trading decision will succeed. Define the question before deciding which datasets belong in the experiment.
In a fictional momentum study, the essential inputs include prices, an eligible universe, a feature date and a later evaluation interval. Collecting more fields will not repair an ambiguous definition of any of those inputs.
Verify the current version
This article was reviewed on October 6, 2026. New integrations should check V2 rather than treating older V1 examples as the current interface. Authentication, endpoint paths and response names need explicit version checks.
The official Python client demonstrates API key authentication for V2. Record the client version and examine a small response before extending an import. Keep credentials outside shareable research records.
Define access and permitted use
Available history and datasets depend on the applicable service terms and subscription. Inspect actual coverage instead of assuming that a requested date interval was delivered completely.
A historical observation date does not establish when that record first became available. Use fictional examples for public explanations and follow the applicable contract when storing or sharing provider data.
Separate market and company observations
Prices describe market observations; financial reports describe a company over a reporting period. Joining them on a shared-looking date can accidentally place unpublished information in a feature.
If a fictional company announces March results in May, those results cannot inform a March decision. Distinguish period end, disclosure and local receipt when determining availability.
Connect to the documented course
KabuForge's public GUI course validates explicitly selected local daily bars and freezes an input before research. That course does not certify that every J-Quants dataset can be imported into the same screen.
The documented runs remain research-only with unverified historical availability. Check the selected file, universe, dates, price basis and run receipt before interpreting features or evaluation results.
Further reading and official references
Continue with Price Data Fields and Observation Dates, Disclosure Times and Financial Revisions, Factor Analysis: Inputs and Evaluation to connect input definitions, availability and evaluation. All numerical and company examples in this article are fictional teaching examples. For real input, prioritize the documentation for your version and your own acquisition and execution records.
Check the official KabuForge GUI research course for documented workflow scope, and JPX: J-Quants datasets, JPX: V2 and delivery-format update for provider documentation or current official implementation. Confirm exact units and access limits against the applicable official specification and contract. General research design guidance does not establish that every proposed check is implemented in the GUI.
This article is educational and does not recommend securities or trades, or guarantee returns. Historical research in the public course does not fully establish that only historically available information was used. Read the disclaimer.
Continue this topic
Applies to: main source candidate (unpublished) · Public source docs/en_US/GUI_RESEARCH_COURSES.md
Reviewed · KabuForge