The National Diet Library (NDL) plans to renew the web services of the National Diet Library Web Archiving Project (WARP) in December 2025.
This page provides information about the renewed web services, major changes, and the impact of the renewal on services.
The core framework of our service?regularly collecting and preserving websites and providing them in their original form?remains unchanged. There will be no changes to the scope of collection or collection frequency.
We have highlighted the features and functions on each webpage that have been redesigned as well as functions that are now different from the current version.
In addition to the keyword search function on the home page, we currently have an advanced search function that enables searching for specific parameters. The new home page will feature an integrated search function that combines a keyword search function with filters for narrowing down search results.
The default search settings target websites archived within the last 5 years.
Search results currently include a Metadata and a Full Text tab. The redesigned search results will by default display full-text search results for archived websites.
Visitors will be able to group search results by URL, website publisher, or other criteria.
The banner at the top of the page indicating a site that has been archived has been redesigned with a purple motif. This banner also appears when viewing archived PDF files.
A Go to Link Source button in the banner enables visitors to view the source linked to the page currently being viewed.
For instance, a visitor viewing a PDF brochure of an event will be able to navigate to a webpage showing the details of the event by clicking this button, which is linked to where that PDF file is posted.
The banner will indicate the availability of printing at National Diet Library facilities. This availability is not currently indicated but will be included in the redesigned banner.
The details page shows a thumbnail of the top page of an archived website, thereby providing a preview of the website. Additionally, buttons at the top of the details page enable direct navigation to websites sorted in descending chronological order: latest archived date, 1 year ago, 3 years ago, or oldest.
A details page has been added using metadata to e-magazines, e-books, and event pages contained in archived websites. Please be aware that metadata for e-magazines, e-books, and other content in archived websites will be added incrementally after the unveiling. Metadata is searchable via the National Diet Library Search.
The URLs used to access the archived websites will change as follows. Please note that as described in "Automatic Redirect to New URLs" if you are using the current address in your links, there is no need to change them to the new URL.
Until now, both https://warp.da.ndl.go.jp/ and https://warp.ndl.go.jp/ were accessible, but after the renewal, access will be unified to https://warp.ndl.go.jp/.
Previously, you had to specify a unique number assigned for each archived date. After the renewal, we will discontinue the unique numbers and change to URLs that include the archived date and time.
The "20230704180734" in the URL after the renewal indicates that it was archived on July 4, 2023, at 18:07:34.
After the renewal, the current address will be permanently and automatically redirected to the new address. Therefore, you do not need to change links to pages or files saved in WARP to the new address.
By linking to a URL with the archived date and time portion set to “latest,” as shown in the following example, you can navigate to the latest page saved in WARP at that point in time.
https://warp.ndl.go.jp/web/latest/https://www.kodomo.go.jp/
We will delay the publication of websites archived after September 2025.
Typically, archived websites are published by the end of the month following their archiving. However, due to system renewal work, websites archived after September are scheduled for publication in January 2026 or later.
Starting October 2025, the source IP address for collection will change due to an update to the communication line for collection.
Some institutions have granted access to the National Diet Library's collection crawler; however, the IP address for which permission is granted will change.
Please contact us for the new IP address.
For inquiries regarding the renewal, please contact the NDL Web Archiving Project (Contact Information)
