One File · Powerful health tracker
Every reading.
Every meal. Time in range.
A diabetes log in one HTML file. Glucose readings, time-in-range %, estimated A1c — for the type-1 or type-2 diabetic who wants their data in their hands, not in a CGM company's cloud.
One payment · Yours forever · 14-day refund
- Works fully offline
- Installs as an app (PWA)
- No account, ever
- Yours, forever
Loads once, never needs the internet again. On a plane, in a basement, in a foreign hotel.
Every entry, every chart — stored locally. We never see it. We can't.
No subscription. No upgrades. No re-up next year. One file, yours.
Why log
Why diabetics end up keeping their own records.
The endo wants 14 days of data; you don't want it in their cloud.
Time-in-range is the gold-standard metric.
The dashboard banner computes 14-day TIR vs. your target window. Clinical guideline is 70%+; the banner tells you whether you're hitting it.
Estimated A1c without a blood draw.
ADAG formula on rolling 90-day average. Same number your endo measures, same direction, same trend.
Context per reading is the diagnosis.
Fasting / pre-meal / post-meal-1h / post-meal-2h / bedtime / exercise / hypo. The patterns reveal what no single number can.
Print-ready for the appointment.
CSV or print straight from browser. Better than handing the endo a phone.
morning + evening cadence
real-distribution data
no recurring fee, ever
no cloud has your bloods
Inside the file
Eight things you'll use every day. Plus a dozen more.
One file. One dashboard. Every feature you'd expect from a "real" app — without the cloud, the cookies, or the £8/month.
Quick add
Log a reading from the home screen — three taps and back to your day.
Live insight banner
The single number that matters today, computed in real time from your entries.
Streak calendar
Daily streak across the last weeks. Showing up becomes the default.
Readings by context
Visual split across categories so the pattern becomes obvious without squinting.
Searchable, sortable list
Every entry findable in seconds — search across notes, sort by anything.
Free-form notes
A textarea per entry for the things that don't fit a field.
PNG share cards
One-tap share card of your stats, ready for Instagram or a group chat.
Cross-entity links
Reference one entity from another — relationships stay intact across edits.
Offline, always
Loads once, runs forever without a network connection.
Installs as a PWA
Add to home screen — opens like any native app.
CSV in / CSV out
Bring your old data in. Take everything with you. No lock-in.
No account, ever
No email, no signup, no analytics, no third-party tracking.
Yours forever
If we vanish tomorrow, your tracker keeps working — local file, no server.
Light + dark
Auto-follows the system. Or pick one and stick with it.
Today
Today, at a glance.
The home screen pulls together what just happened and what's coming up — clean enough to actually look at every morning.
- Live insight banner — your unique angle, computed from your entries
- Four-tile stat grid surfacing the numbers that matter today
- Streak calendar showing the last weeks at a glance
- Quick-add button — log without leaving the home screen
- Recent entries on the dashboard so the last log is one tap away
Readings
Every reading, in one place.
Date, time, blood glucose (mmol/l), context per row. Sortable, searchable, groupable.
- Search across notes
- Sorted by date (newest first)
- Group by context with one tap
- 8 fields per entry — the right amount of detail
How it's different
What you give up vs. CGM apps. Auto-pulling readings from a sensor.
Compared with CGM and diabetes platforms.
- Pricing modelPay once · $6.99£8 – £15 / month, forever
- Account requiredNoYes
- CGM auto-pullNoYes
- TIR + estimated A1cYesYes
- Print-ready for clinicianYesLimited
- Data stays on your deviceYesNo
- Insurance partner integrationNoYes
The promise
Your bloods are yours.
Not a CGM company's training set.
Offline, always
Open it once, never need the internet again. The file holds the whole app.
Local-first storage
Every entry stored in your browser, on your device. No server sync. No leaks. Nothing to breach.
One payment, forever
No subscription, no upgrade tier, no nag. If we shut down OneFileClub tomorrow, your file keeps working.
Data does not sync automatically between phone and desktop
This is a local-first app — everything stays on the device you logged it on. To use it on both phone and desktop, use the built-in JSON or CSV export on one device and import on the other when you want to keep them in step.
Every view, light and dark.
A look at every screen across both themes — your tracker, populated.
Questions
Real answers, no fine print.
Is this medical advice?+
No. The TIR + estimated A1c are mechanical (using published clinical formulas). Your endo / diabetes nurse interprets — the file gives them clean data.
Pulls from my CGM?+
No — the trade-off is total privacy. Most CGMs export CSV; manual entry takes minutes per fortnight, and the act of writing is reflective.
Where is my data stored?+
Locally, in your browser, on your device. Nothing is sent to OneFileClub or anyone else — there is no account, no cloud sync, no analytics.
Does it work offline?+
Yes. Once your personalised copy loads the first time, the entire tracker runs from a single HTML file. Airplane mode is fine.
What does 'personalised copy' mean?+
When you buy, OneFileClub stamps a private copy with your licence and deploys it to a unique URL just for you. You bookmark it, install it as an app, or save the file — and the file is yours, even if OneFileClub disappears tomorrow.
What is your refund policy?+
14 days, no questions asked. Email us, we'll process it and disable your private URL.
One payment.
A logbook for the long haul.
We'll personalise a copy and email you a private link. Bookmark it, install it as an app, log tomorrow morning's reading.
14-day refund · No subscription
