Your file stays
in your browser.

CSV input and reports

The checker does not send file contents to an application server, save them in browser storage, or put them in a page URL. Input and results stay in the current page's memory and are discarded when it is reloaded or closed. Exported reports are saved through your browser and can contain original values, including sensitive information from your file.

If you use an AI browser integration to provide CSV text, that integration's own data handling also applies. The site's optional check_csv tool performs the same local check and returns selected findings to the calling agent. Do not give an AI service data you do not want it to receive.

Website hosting

Page and asset requests still reach the hosting provider, which may process ordinary connection information such as IP address, browser information and requested URL under its own policies. Local CSV processing does not mean browsing the website is anonymous.

We do not provide an email collection form. Hosting access controls and browser extensions operate separately from our checker.

Visit measurement on Column Harbor

From October 20, 2026, csv.jhsoftlabs.com uses Cloudflare Web Analytics to understand visits, page views, referring websites and loading performance. A browser measurement script sends this information to Cloudflare. The service does not use analytics cookies or track a person across websites; ordinary network requests still reach the provider.

We do not send CSV contents, filenames, column names, cell values, generated reports or saved settings to analytics. We do not add form recording, session replay or custom tool-input events. The tools continue to process your files locally and work if the measurement script is blocked.

Referring-site and public-page reports help us understand how people find these resources. A missing referrer does not identify a specific source, and blocking or network failures can leave visits uncounted. These reports do not reveal every AI citation or recover visits from before measurement began. Cloudflare currently omits query strings from its analytics reports, so campaign parameters are not a separate attribution report.

Read the Cloudflare Web Analytics documentation and Cloudflare privacy policy for the provider's data handling.

JH Soft Labs homepage

The separate homepage at jhsoftlabs.com uses Cloudflare Pages hosting and Cloudflare Web Analytics to understand page visits and loading performance. Its analytics beacon sends measurement requests to Cloudflare. Ordinary page requests also reach the hosting provider. This is separate from the local CSV tools described above.

The homepage places its collection filter and search text in the page URL so a view can be shared. Do not enter confidential information there: URLs can appear in browser history, copied links and hosting requests. Its release checklist keeps selections in page memory and offers a local text export; it does not submit those selections to us.

See Cloudflare Web Analytics documentation and Cloudflare's privacy policy. Links to the interview and image services, Medium, X and other external services have their own data handling; this notice does not describe their application features.

Saved tools and resources

Workspace can save the identifiers of tools, formulas and resources you bookmark in this browser’s local storage. These saved items contain links only, never file contents, pasted values, results or filenames. They do not sync between devices. Clear them from the Saved view or through your browser’s site-data settings. The tools remain usable if local storage is unavailable.

Repeat-cleanup settings

The repeat-cleanup tool can save a versioned set of numeric column positions, expected column counts and operation switches in this browser's local storage when you choose Save settings. It does not store column names, filenames, cell values, input files or results. These settings do not sync and are never added to URLs or submitted to a server. Review the current column mapping before using settings on another file. Use Clear saved settings in that tool or clear this site's browser data to remove them. Blocked storage does not prevent running the tool.

Excel Academy progress

Excel Academy keeps the identifiers of lessons you mark complete and your last visited lesson in this browser’s local storage. It does not store quiz answers, learner names or workbook contents, and does not sync between devices. Use Reset progress on the Academy overview to clear this checklist. If browser storage is blocked, you can still read every lesson and use its exercises.

Advertising and your choices

Our editorial guides include Google AdSense code. Ads depend on Google approving the site and making ads available. Google and its advertising partners may use cookies, device identifiers, IP addresses and browsing information to deliver, personalize and measure ads. We do not send CSV input or checker results to Google advertising. The checker, Workspace, Excel Academy, this privacy page and the guide directory do not include our advertising code.

For visitors in the European Economic Area, the United Kingdom and Switzerland, Google's consent message provides consent, refusal and options controls. When available, use the "Privacy and cookie settings" link at the bottom of a guide to revisit your choice. Blocking ads or declining personalization does not prevent reading our guides.

Learn how Google uses information from sites using its services, review Google's advertising policies for users, or manage personalization through My Ad Center. You can also delete or restrict cookies in your browser; doing so may require you to make your consent choice again.

Links and feedback

Documentation and X contact links lead to other services with their own privacy policies. Feedback you choose to send through X is handled there; the site has no feedback database. Use synthetic examples instead of customer data when reporting an issue.

For questions, contact @sashimi_mong on X.