Application Programming Interface (API) of the NDL Search: Application Form

People who wish to apply for the Application Programming Interface (API) of the NDL Search are requested to fill in the form and return it online to the National Diet Library.
We cannot go through the application procedure with any requirement undefined. Please fill out all necessary information in the application form.
We will inform you of details of the next procedure after confirming your application.
Please note that we may ask more details about the utilization of API depending on the content of your application by e-mail.

1.About Applicant

Applicant [Required]
Name of institution [Required]* If your institution has a website, please also enter its URL.
Name of the person in charge [Required]* Enter the name and position of the person who represents the whole organization (such as the president or department head).
Postal address [Required]
Name of contact person [Required]
E-mail [Required]* Enter E-mail which can receive attachment files.

(For confirmation)
Phone number [Required]

2.About your service which utilizes API

Name of your service [Required]
URL of your service [Required]* If your service does not have a URL, enter the means to confirm your service, or the reason like "The service is not open to the public because it is used within our company only."

3.Main actor of constructing your service

Name of the actor (institution or individual) [Required]* If you apply as an institution, enter name of institution.

4.Purpose, outline, etc. of your service

Purpose of your service [Required]* Describe main purpose of whole of your service.
Outline of your service [Required]* Describe function of your service and how it utilizes API.
Profit [Required]* A business entity should select "for profit" even if your service is free of charge.
Fees for your service [Required]
Number of users of your service [Required]* If you are going to start a new service, enter the estimated number.
Revision of the fee in accordance with the implementation of API  [Required]
If you are going to revise the fee by the implementation of API, please describe the basis of calculation. [Required]


API(s) [Required](Select one or more)

6.Database and data item(s) to be utilized

Name(s) of the database for a search request [Required]* Please specify name of each database like "NDL Online," "NDL Digital Collections," etc.
* Not all databases (data providers) can be searched by all APIs. For details, please refer to "List of Data Providers Available by API".
Name(s) of data item(s) to be utilized [Required]* Please specify names of all data item(s) like "Title," "Creator," etc., or describe a range like "all the data items which can be returned by above API" for each API to be utilized.
* About the data items which can be returned by each API, please refer "Appendix3.Examples of returned data at each interface" of "NDL Search API Specifications".


If you have any questions or comments about the permission procedure for API, please fill in the following:
* If you have any question about the function of API, please use Request Form.
Treatment of personal information
  • The personal information that you have entered will be used only for the respond to your inquiry and not be used for any other purpose.
  • For information on policies related to the protection of personal information, please refer to "Private policy «About National Diet Library search."


  • We will immediately send you an automated response to confirm that we have received your request. Please check if you are set up to receive emails from (at) .
    *Please replace the (at) with @.
  • If a message such as "Please input alphanumeric characters into [●●●●●]" or “The platform dependent character is included in "[●●●●●]" is displayed, your input may include machine-dependent characters, pictograms, etc. Please correct the input by replacing the characters that caused the error with characters that are permitted.

Contact information

Digital Information Distribution Division
Digital Information Department
National Diet Library, Japan

e-mail: di-api(at)
*Please replace the (at) with @.

NDL Policies

For information on NDL policies regarding the protection of personal information, please refer to the links below.

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