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Documentation Index

Fetch the complete documentation index at: https://docs.getbased.health/llms.txt

Use this file to discover all available pages before exploring further.

getbased includes eight measurement utilities for characterizing your light environment. All processing runs in your browser — camera frames and sensor data are never sent to a server. Access all tools from the Light & Sun page under the Light tools section.

Tools at a glance

ToolWhat it measuresBest used for
Lux MeterAmbient brightness in luxSetting up a workspace, comparing rooms, verifying outdoor exposure levels
Flicker DetectorPWM banding at 240 fps + risk scoreIdentifying problem bulbs and screens causing eye strain
CCT MeterColor temperature in Kelvin + solar coherence checkCatching evening blue-light contamination from indoor lights
Spectrum Classifier5-category light source identificationAuto-filling room type in the Light Environment survey
Glass TransmissionInside-vs-outside brightness ratio + UV transmission estimateAuditing how much light your windows actually block
Sleep DarknessLong-exposure lux reading at pillow levelChecking whether your bedroom is dark enough for full melatonin
Sunrise LoggerOne-tap sunrise / sunset session entryCapturing routine golden-hour outdoor light
Eye-Level AuditRoom-by-room lux walkthroughPopulating your full Light Environment in a single 10-minute pass

Tool 1 — Lux Meter

Measures ambient brightness in lux. Uses your phone’s AmbientLightSensor API when available (Chrome on Android), with a camera-based estimate as a fallback on other browsers. Color-coded zones help you interpret readings:
Lux rangeZone
0–10Darkness (full night)
10–100Low indoor (dim room)
100–500Office (well-lit computer work)
500–1,000Bright indoor
1,000–10,000Overcast outdoor
10,000–100,000Outdoor daylight
100,000+Direct sun
The camera fallback uses a calibration multiplier stored locally. It defaults to 1.0 and reads within ±30% of a reference meter on most modern phones. If you have a calibrated lux meter, you can dial in the multiplier for more accurate absolute readings.

Tool 2 — Flicker Detector

Aim your camera at a light source. The live preview shows banding patterns if the light is flickering. Flicker comes from pulse-width modulation (PWM) dimming, which is common in LEDs and fluorescent lights. After roughly five seconds of capture, you get:
  • A score from 0 (flicker-free) to 3 (heavy flicker)
  • An estimated PWM frequency in Hz
  • A plain-English label: Flicker-free / Mild, likely OK for most / Visible flicker — eye-strain risk / Heavy flicker — replace this light
Risk thresholds follow IEEE Std 1789-2015 recommended-practice limits for LED current modulation.
Dimmable LEDs are the most common source of household PWM flicker. If flicker is detected on a dimmable fixture, a non-dimmable or DC-dimmable replacement is typically needed — dimmer adjustments alone won’t fix it.

Tool 3 — CCT Meter

Aim at a white wall, a sheet of paper, or a printable grey card. The tool gives you a live color temperature estimate in Kelvin — from 1,800 K (candlelight) up to 6,500 K and above (overcast sky / daylight). Estimates use RGB white-balance ratios from the camera. The solar coherence indicator compares your indoor CCT to the approximate solar color temperature for the current hour:
  • Matches solar time — within 800 K of the expected solar CCT
  • Slight mismatch — noticeable gap but not severe
  • Mismatch — your indoor light is working against the sun’s signal (for example, a 4,000 K cool LED at 9 pm when the sun set hours ago)

Tool 4 — Spectrum Classifier

Single-tap classification. The tool uses your camera’s RGB ratio and flicker variance signature to categorize the light source into one of five types:
  • Fluorescent / CFL — high flicker variance with a green color spike
  • Incandescent / halogen — red-rich, low blue
  • Cool LED (4,000 K+) — blue-rich, near-flicker-free
  • Warm LED (2,700–3,000 K) — slight red lift, near-flicker-free
  • Daylight or full-spectrum — balanced RGB
Confidence is shown alongside the result. Use this tool to auto-fill the light source type when you’re adding a new room to your Light Environment.

Tool 5 — Glass Transmission

Measures how much light your window actually blocks. The flow has two steps:
1

Measure inside

Point your phone through the glass at the brightest part of the sky.
2

Measure outside

Move outside and aim in the same direction with no glass between you and the sky.
The app computes the transmission ratio between the two readings. Most modern Low-E coated glass blocks 80–90% of UV and 30–50% of visible light. Tinted automotive glass typically blocks more. This gives you a real number for how much your windows reduce the cellular repair channel — and lets the AI factor your specific glass into your indoor exposure estimates.

Tool 6 — Sleep Darkness

Place your phone face-up at the position where your eyes will be when you sleep. Set the room conditions to match how you actually sleep. Tap Start — the tool runs a 30-second long-exposure read.
Lux readingAssessment
< 0.3 luxExcellent — true darkness
0.3–1 luxGood — minor light leak, melatonin mostly preserved
1–5 luxLight leak detected — ~20–30% melatonin attenuation
> 5 luxBright — melatonin amplitude significantly suppressed
If your sleep quality is poor and your bedroom scores above 1 lux, light is the first thing to address — before supplements or sleep timing changes.

Tool 7 — Sunrise Logger

One-tap session entry for sunrise and sunset windows. The tool auto-labels the time window (Sunrise / Sunset / Golden hour) based on the current hour and pre-fills a typical exposure: face and hands, with direct eye exposure, for roughly 15 minutes. This is the most circadian-effective outdoor light most people get on a typical day, and it’s the easiest to consistently log.

Tool 8 — Eye-Level Audit

A 10-minute room-by-room camera walkthrough that populates your entire Light Environment in one pass. The camera streams at 4 fps and detects when you’ve paused in a room (5 seconds of stillness), capturing a lux reading at eye level. After your walk:
  1. Review the list of pauses on the after-walk panel
  2. Label each pause with the room name
  3. Tap Done
Labelled pauses are saved as lux measurements bound to the matching room — creating a new room automatically when no match exists. Unlabelled pauses stay in the bulk audit record for later review.
Tool 8 captures lux only, not CCT or full spectrum. The goal is fast full-home coverage. For richer data on a specific room — flicker, color temperature, sleep darkness — open the dedicated tool from that room’s card after the walkthrough.

How measurements are stored

Measurements are stored as a latest-per-room-per-tool record. When you measure the same room with the same tool again, the new reading replaces the old one. This keeps the dataset clean and ensures the AI always works from your most current readings. Eye-Level Audit walkthrough records are an exception — each walkthrough is stored as its own record so you can compare runs over time. All measurements are stored locally on your device. They sync to your other devices via Evolu CRDT only if you’ve enabled cross-device sync, and the sync payload is end-to-end encrypted. Camera frames and sensor readings are processed in-browser and discarded — they never reach a server.