Zenken
Zenken rolls out ChatGPT Enterprise to all staff and reports about 12,500 hours saved a month
Zenken, a Tokyo-listed marketing, overseas-talent and real estate group, gave all employees ChatGPT Enterprise from November 2024. An internal survey three months later estimated about 12,500 hours of work saved a month, and the company reports about 50 million yen lower outsourcing costs in 2024.
Key figures
Copied exactly from the sources. Copy any figure with its citation.
about 12,500 hours
Work effort reduced per month, from an internal survey three months after the company-wide rollout (Japanese: 月間約12,500時間分の工数が削減)1
about 2x
Productivity improvement reported by survey respondents, on average1
380
Valid responses to the internal survey3
about 50 million yen
Reduction in outsourcing costs across 2024 versus the prior year, including the pilot period (Japanese: 約5,000万円)1
What it took
The problem
Zenken is a Tokyo-listed group in marketing, overseas talent and real estate. It spent money on outside contractors and wanted staff to spend less time on routine work. It looked for a tool that could be used across sales, accounting and administration.
What they built
Zenken gave every employee ChatGPT Enterprise, OpenAI's business version of ChatGPT. Staff use it in different departments. Examples named by Zenken's roundup page include accounting questions, sales research and drafting, and searching internal system manuals.
How they did it
Zenken began with a pilot among some employees in January 2024. It rolled the tool out to all employees in November 2024, taking a bottom-up approach. The company says it won budget approval by pointing to lower outsourcing costs. Three months after the company-wide launch it ran an internal survey, which drew 380 valid responses.
Results
In that survey, respondents estimated that about 12,500 hours of work were saved each month and that productivity roughly doubled on average. Zenken also reports that its outsourcing costs for 2024, which includes the pilot period, were about 50 million yen lower than the year before. The coki.jp news site repeated these figures in April 2025.
Lessons for your project
Frame the business case around a cost you already pay. Zenken pitched the budget as a way to cut outsourcing spend, and reports about 50 million yen lower in 2024.
Pilot with a few employees before going company-wide. Zenken started in January 2024 and expanded in November.
Survey users after about three months and say plainly that the hours saved are self-reported estimates.
Treat hours saved as capacity, not cash. Decide what the freed time goes to, such as customer work or new offers.
Caveats
- The figures come from Zenken's own announcement and an internal survey. The hours saved and the doubling of productivity are respondents' estimates, not measured time.
- The outsourcing saving covers the whole of 2024, including the pilot period, and is not attributed to a single cause by the sources.
- The survey's 380 valid responses are stated on a Zenken-run roundup page. The release itself does not give a sample size.
- The coki.jp article reports the same Zenken figures and is not an independent audit of them.
- Zenken's AI media site, where the release is mirrored, is run by Zenken itself.
- The sources do not name a specific model. ChatGPT Enterprise is the product.
Sources
- Zenken、ChatGPT Enterprise全社員導入で年5,000万円の外部委託費用削減を実現！
Zenken AI (Zenken) · 2025-04-24 · Press release · ai.zenken.co.jp
- Zenken、生成AIで月1万2千時間の業務削減、年5千万円の費用削減
coki · 2025-04-28 · News · coki.jp
- 日本企業のChatGPT Enterprise導入事例
Zenken AI (Zenken) · 2025-09-17 · Company blog · ai.zenken.co.jp
Summarized in our own words from the sources above. Spotted an error? See corrections.