Built by students. Measured in minutes. Open to everyone in Bangladesh.

One Drop is planned, written and maintained by students of Notre Dame College, Dhaka — Batch 27. Free forever, volunteer-run, and designed for the moments when a hospital says “we need blood now.”

Why we built it

Started from a phone call that came too late

Like most things that matter, it began with a bad night. A relative of one of our classmates was admitted after a road accident, and the blood bank asked for two bags of O− by morning. What followed is what always follows in Bangladesh: a panic of phone calls, forwarded contacts, half-remembered numbers — while the clock kept moving. The blood arrived in time. But it left us with a question we could not put down: why was there no single place to ask, “who near me can donate today?”

One Drop is that place. Registering as a voluntary donor takes under a minute. Searching the directory needs no account at all. And when a family posts an emergency request, every volunteer with alerts enabled hears about it at the same moment — not one forwarded phone call at a time.

We are not a blood bank. We do not collect, screen, store or transport blood. We shorten the distance between a request and a willing arm — and we do it while keeping donors’ phone numbers off the public page.

Ground rules we follow: every listing is voluntary, unpaid and non-commercial. Selling blood is illegal in Bangladesh and against everything this project stands for. Moderators remove any listing that looks fake, paid or misleading.

Field notes

What this looks like under pressure

Three composite scenes, assembled from situations families have described to us. Names and details are changed; the sequence is exactly how the tools on this site are designed to behave.

02:40 — postpartum haemorrhage, Dhaka The hospital needs O− within the hour and the family knows nobody with that group. From the waiting room they post a request. Three volunteers with alerts on see it immediately; the nearest — a student four kilometres away — taps “Offer to donate”, calls the attendant to confirm, and reaches the blood bank before shift change. The request is marked fulfilled at 04:05.
A regular transfusion, a reliable circle A thalassemia patient needs blood every third week. Instead of rebuilding a contact list each cycle, the family searches the directory and quietly builds a small rotation of willing donors. The 56-day cooling-off tracker means nobody is ever asked too soon — and each donor can see for themselves exactly when they become eligible again.
When the exact group isn’t available A district shows zero exact-match donors at 2 a.m. The compatibility chart becomes the most valuable thing on the page: the family calls two compatible-group donors instead of waiting for an impossible match, and the blood bank later confirms the alternative was precisely what they would have requested.
Reference

Red-cell compatibility chart

Use this to decide which donors are worth calling first. Final decisions always belong to the treating doctor and the blood bank.

✓ = compatible for red-cell transfusion
Patient needsA+A−B+B−AB+AB−O+O−
Credits

The people behind One Drop

Idea & initiative Students of Notre Dame College, Dhaka — Batch 27. Research, planning, writing, and day-to-day community moderation.
Volunteer moderators Classmates who verify listings by phone, review reports, and keep the emergency board accurate and honest.
Technology Deliberately simple: hand-written HTML/CSS/JS, Firebase Authentication and Firestore, and a service worker for offline use. No trackers, no advertising, no data sold — ever.

Want to help? A directory is only as strong as the donors inside it. Share this site with your class, your hall, your mosque and temple committees, your neighbourhood group — or join the One Drop WhatsApp community and forward the requests that match your friends’ blood groups. Corrections and suggestions are always welcome through the contact form.