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 plan to update the design of pages such as the top page, the banner displayed at the top of the archived contents, and the search function. Details will be posted on this page in November.
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)
