One bulb died.
Buy the one that matches.

Point your iPhone at a bulb in the fixture that still works, and BulbMatch tells you which standard bulb to buy — 2700K, 3000K, 4000K or 5000K — then saves it under that room so the next one is a lookup instead of a guess.

Download on the App Store

Same words. Different bulbs.

The number on the dead bulb is burnt off, or the bulb is already in the trash. So you read the box — and the box is where it goes wrong. Here is what US retail actually prints on each temperature.

2700K
BulbMatch shows
Warm White
Sold as
  • Soft White
  • Warm White
  • Warm Glow
3000K
BulbMatch shows
Soft White
Sold as
  • Warm White
  • Bright White
  • Soft White
4000K
BulbMatch shows
Cool White
Sold as
  • Bright White
  • Cool White
  • Neutral White
5000K
BulbMatch shows
Daylight
Sold as
  • Daylight
  • Natural Daylight

Highlighted phrases are printed on more than one temperature.

“Soft White” is printed on 2700K bulbs and on 3000K bulbs. “Bright White” is printed on 3000K and on 4000K. The words are not a mistake and they are not going away — brands simply don’t agree on them. That is why reading the box narrows it to two answers and can’t pick one, and why the replacement glows yellower than its neighbors. BulbMatch leads with the Kelvin figure, the half everyone agrees on, and then lists every phrase that bulb is sold under so you can match whatever the shelf calls it.

Why BulbMatch?

Built for the person standing in the lighting aisle with a dead bulb in their hand — not for a film crew.

💡

An Answer You Can Shop With

Not chromaticity coordinates or gel numbers. “2700K · Warm White,” plus every phrase that bulb is sold under, so you can match the box in front of you.

⚖️

It Says When It Isn’t Sure

Nothing appears until the reading holds still. When two temperatures are genuinely in play it tells you — “Between 2700K and 3000K — measure again on white paper” — instead of picking one and hoping.

🏠

Rooms Remember

Save the fixture once with its room, bulb count, and base type. The next time one goes, it’s a two-second lookup, and a shopping list you can copy before you leave.

📄

Two Ways to Read

Aim at the lit bulb, or use the guided white-paper method — hold plain paper where only that bulb lights it. The paper method is the more reliable of the two.

🔒

Camera Only. Nothing Leaves.

No photo library, no microphone, no location. No frame is ever saved. No account, no analytics, no network layer at all — it works in Airplane Mode.

🏷️

Buy It Once, Or Not At All

Three measurements free to see whether it helps. $4.99 once if it does. No subscription, no trial to remember, and no ads anywhere in the app.

How it works

Three steps. After that it’s a lookup.

1

Point at a Bulb That Works

In a three-bulb fixture, one still burning is all you need. Aim the rear camera at it while it’s lit — or switch to the guided white-paper method and read the light off the page instead.

2

Wait for It to Settle

The reading stays grayed out while it moves. Once it holds still, BulbMatch names the bulb: 2700K · Warm White, with the packaging phrases to look for on the shelf. If it won’t settle, it says so.

3

Save It to a Room

Name the fixture, its room, how many bulbs, the base type. Kitchen ceiling: 3 × 2700K, E26. Next time one blows, you already know what to buy.

BulbMatch reads the light your camera sees, so a reading from one iPhone isn’t comparable to a reading from another, or from a different camera on the same phone. It records which device took each one and tells you, rather than quietly mixing them together. The bulb has to be on, and the camera has to see it or the paper it’s lighting.

Simple pricing

Three free measurements to find out whether it helps. One payment if it does.

Free

$0
No account required
  • 3 measurements, total
  • The answer, and what the box will call it
  • Guided white-paper method
  • 1 saved fixture
  • No ads
  • Unlimited measurements
  • Unlimited rooms and fixtures
  • Calibration
  • Measurement history
  • Copy a shopping list
ONE-TIME PURCHASE

Unlock

$4.99 once
Paid once. Nothing renews.
  • Unlimited measurements
  • Unlimited rooms and fixtures
  • Calibration against a bulb you know
  • Measurement history per fixture
  • Copy a shopping list before you leave
  • Family Sharing included
  • No ads

This is not a subscription. There is no trial, nothing renews, and there is nothing to cancel — you pay $4.99 one time and the unlock stays on your Apple Account, restorable on your other devices.

Stop guessing
in the bulb aisle.

Read a bulb that still works, find out what to buy, and save it to the room. On your iPhone, on-device, with no account.

Download on the App Store