LUX - Illuminance Meter
LUX - 照度計
Not in any tracked top chart right now.
Updated 21 Oct 2026 · rankings refresh through the day
Developerkoji torishima
CategoryProductivity
PriceFree
Released
Rating★ 4.2 (170)
Version2.4.1
Age rating4+
First seen by us
29 Sep 2026
29 Sep 2026Installs (est.)10k+ worldwide
Rating
4.2 ★
170 ratings
Measured
LUX - Illuminance Meter on the App Store
App details
App ID
1631156210
Publisher
koji torishima
On the store since
Jul 2022
4 years on the store
Minimum OS
iOS 18.0+
iPhone XS and later
Devices
iPhone · iPad
Content rating
4+
Languages
2
EN JA
Size
18 MB
Also listed in
Lifestyle
LUX - Illuminance Meter downloads
Worldwide, per day, and installs to date. The band is open; the exact number is free with an account.
How this is calculated
Apple publishes no download counts. iPhone downloads come from chart positions and daily rating growth per country, calibrated on Google Play install counts; lifetime installs from ratings worldwide × installs per rating. Confidence is the chance the real number is within half to double ours.
Where LUX - Illuminance Meter's downloads come from Modelled
Last 30 days: organic search, browsing the store, features and paid ads.
Active users
All platforms, worldwide. Free with an account.
Stickiness (DAU / MAU)
how many monthly users open it on a given day
Retention · share of new users still active
Day 1
Day 7
Day 30
Time spent · per daily user
Average time spent Pro
min a day
Sessions a day Pro
Time per session Pro
min
How this is calculated
Monthly users come from lifetime installs across every store, fitted on monthly active user figures companies publish; daily users = monthly × the typical daily/monthly ratio for the category. Confidence is the chance the real number is within half to double ours.
Where it ranks now
Every top chart it appears in across 30 countries.
| Country | Charts | Rank |
|---|---|---|
| Not charting right now. | ||
Ratings
App Store, worldwide.
Rating
4.2 ★
170 ratings
Measured
Ratings
170
Measured
About LUX - Illuminance Meter
LUX is a light meter app that measures illuminance (lux) wherever you are. Open the app and instantly see how bright your space is.
When to use it
- Check lighting in your living room, office, or study area
- Set up photography or video shoots
- Compare brightness between rooms or times of day
- Verify light levels for plants or aquariums
- Confirm any task has the right brightness
Features
- Instant measurement on launch
- Hold the value or freeze the screen
- Color temperature (CCT / Kelvin) measurement
- Auto-recorded Min / Avg / Max lux during a session
- Foot-candle (fc) unit toggle
- Compare with reference levels by scene (some features need Premium)
- Measurement history (Premium)
- CSV / PDF export (Premium)
- PPFD / DLI calculation for plants (Premium)
- Continuous logging with charts (Premium)
Measurements are processed on-device.
Terms of Use: https://kojitorishima.org/en/products/lux/terms/
Privacy Policy: https://kojitorishima.org/en/products/lux/privacy/
When to use it
- Check lighting in your living room, office, or study area
- Set up photography or video shoots
- Compare brightness between rooms or times of day
- Verify light levels for plants or aquariums
- Confirm any task has the right brightness
Features
- Instant measurement on launch
- Hold the value or freeze the screen
- Color temperature (CCT / Kelvin) measurement
- Auto-recorded Min / Avg / Max lux during a session
- Foot-candle (fc) unit toggle
- Compare with reference levels by scene (some features need Premium)
- Measurement history (Premium)
- CSV / PDF export (Premium)
- PPFD / DLI calculation for plants (Premium)
- Continuous logging with charts (Premium)
Measurements are processed on-device.
Terms of Use: https://kojitorishima.org/en/products/lux/terms/
Privacy Policy: https://kojitorishima.org/en/products/lux/privacy/
Latest updates
2.4.1
What's new
- Lifetime Plan
Unlock every Premium feature for good with a single purchase.
- Save up to 3 measurements for free
Saved measurements appear in the History tab.
- Help on our website
Tap ? on each feature to open a detailed guide on our website.
- Other display improvements and bug fixes
2.4.0
What's new
- Reference Lux by Scene
Pick a place such as a living room or office to see how the current reading compares with the reference level. You can add your own scenes too (some features need Premium).
- PPFD / DLI for Plants
See the light strength plants receive and the total light they get in a day (Premium).
- Continuous Logging
Record lux automatically at a fixed interval and view the changes as a chart. Sessions can be saved to history (Premium).
- PDF Report Export
Export your measurement history as a PDF to share (Premium).
- Easier Measurement Screen
The measure button is now large and centered. Tap ? on each feature to learn how to use it.