US-based Anthropic has launched "claude.com/check-content," a web page that allows users to determine whether a file was created or edited using the AI assistant Claude by simply uploading it.
Product LaunchesAnthropicClaude
Anthropic Releases Web Tool to Detect Generation and Editing by Claude
This article is a translation. Read the Japanese original
This tool is based on C2PA, the industry standard for recording content provenance. If content credentials (metadata recording the history of generation and editing) are embedded in the file, the tool will indicate traces of processing by Claude. It is currently available for free and can be used via drag-and-drop into the browser or by selecting files from a device or Google Drive.
At this stage, detection is limited to image, audio, and video files such as JPEG, GIF, MP3, and MOV, and does not support text formats. Detection for text is planned to be performed using the "Detection API," which is currently in a private preview stage. According to the company, this API is being provided to eligible organizations in accordance with EU law requirements.
Anthropic explains that the watermarking for text generated by Claude does not affect output quality, cost, or appearance. Furthermore, the watermark remains even if the content is moved to another location via copy and paste. The company stated that it may expand the scope of the check tool in the future to align with the expansion of file formats supported by the C2PA standard.
Sources
- Anthropic、Claudeを使ったコンテンツを見分けるツール公開--現時点でテキストは未対応 - Yahoo!ニュース （Google News: Anthropic、2026-09-02）