OIO vs WiZ: Smart Circadian Lighting Compared
WiZ Connected is one of the most compelling budget smart bulbs on the market. At $12–15 per bulb with no hub required and a built-in "Circadian Rhythm" mode, it looks like it solves the same problem as OIO by Korrus at a fraction of the price.
It doesn't. Here's why, and where WiZ does legitimately earn its place.
At a Glance
| Spec | OIO by Korrus | WiZ Connected |
|---|---|---|
| Approach | 4 spectral modes (chip-level SPD) | CCT shifting with scheduling |
| Blue light handling | Removed in evening modes | Blue spike persists at all settings |
| "Circadian" feature | 4 spectral recipes, automated | CCT schedule (warm/cool throughout day) |
| Lumens | 800 | 800–1100 (varies by model) |
| Wattage | 9W | 8.8–10W |
| Color range | 1500K–6500K | 2200K–6500K |
| Lifespan | 25,000 hours | 25,000 hours |
| Hub required | No | No |
| Smart home | Matter, Alexa, Google, Apple Home | Alexa, Google (Matter on newer models) |
| Parent company | Korrus (500+ patents) | Signify (same parent as Philips Hue) |
| Clinical data | 68% more melatonin (Salk Institute) | None published |
| Price per bulb | $30–35 | $12–15 |
| Availability | korrus.com | Amazon, Home Depot, retail |
WiZ's "Circadian Rhythm" Mode: What It Actually Does
WiZ has a feature called "Circadian Rhythm" built into its app. It sounds exactly like what OIO offers. It isn't.
WiZ's circadian mode shifts color temperature throughout the day — cooler in the morning, warmer in the evening. That's it. It's a scheduled CCT ramp. The underlying LED technology is standard phosphor-converted white, which means the characteristic blue emission spike around 450–460nm persists at every color temperature setting.
The CCT trap: WiZ (and its sibling Philips Hue) both use CCT shifting marketed as "circadian." But color temperature tells you what the light looks like to your eyes, not what it does to your biology. Your intrinsically photosensitive retinal ganglion cells (ipRGCs) respond to specific wavelengths, not to "warmth." A 2200K LED that still emits a blue spike will still suppress melatonin. WiZ's circadian mode makes the light look warm. It doesn't make it biologically safe for nighttime.
OIO's approach is fundamentally different. Instead of shifting color temperature on a standard LED, Korrus engineers the spectral power distribution at the chip and phosphor level. In OIO's ZeroBlue evening mode, blue wavelengths are physically absent from the output. They're not dimmed, not filtered, not masked by warm phosphors — they're not emitted.
This is the difference between turning down the blue channel on a monitor (it's still there, just dimmer) and removing the blue LEDs from the backlight entirely.
The Signify Connection
WiZ is owned by Signify, the same company that makes Philips Hue. WiZ is essentially Signify's budget smart lighting line — WiFi-based instead of Zigbee, no hub required, simpler features, lower price. The LED technology is fundamentally the same as Hue: standard phosphor-converted white LEDs with CCT tuning.
This means WiZ shares the same circadian limitation as Hue: the blue spike is baked into the hardware. No amount of software scheduling can remove it.
Where WiZ Wins
WiZ has genuine strengths, and for certain use cases it's the better buy.
- Price. At $12–15 per bulb, WiZ is less than half the cost of OIO. For a 10-bulb home, that's $120–150 vs. $299.99. If you're on a tight budget and just want smart lights, WiZ is hard to beat.
- No hub required. Like OIO, WiZ connects directly via WiFi. Unlike Philips Hue, there's no $60 bridge to buy.
- Broad availability. Amazon, Home Depot, Walmart, and other retailers carry WiZ. Easy to buy, easy to return.
- Decent app. The WiZ app is functional and well-designed for a budget product. Scheduling, scenes, and room grouping all work as expected.
- General smart lighting. If you want inexpensive smart bulbs for general use — voice control, scheduling, scenes — and circadian biology isn't your primary goal, WiZ is an excellent value.
Who should buy WiZ: If you want affordable smart lights that you can schedule and voice-control, and "circadian" is a nice-to-have feature rather than your primary motivation, WiZ is a strong choice. It's good at being a budget smart bulb. It's not good at being a circadian bulb.
Where OIO Wins
- Actual spectral engineering. OIO removes blue wavelengths at the chip level. WiZ cannot. This is the fundamental reason to choose OIO over any CCT-shifting bulb.
- 4 distinct spectral modes. MaxBlue for morning alertness, Daylight for work, ZeroBlue for evening, Deep Warm 1400K for pre-sleep. Each is a different spectral recipe, not just a different color temperature.
- Clinical evidence. 68% more melatonin under OIO's evening mode vs. standard LEDs, measured at the Salk Institute with Satchin Panda. WiZ has no published circadian data.
- Deeper warm range. OIO goes down to 1500K (Deep Warm mode at 1400K). WiZ bottoms out at 2200K. Those 800 degrees matter — it's the difference between a warm-ish white and a deep candle-like amber.
- 500+ patents. Korrus traces its technology to Shuji Nakamura's Nobel Prize-winning work on blue LEDs. This is deep materials science, not a software feature.
- Matter support. OIO supports Matter from day one. WiZ has added Matter to some newer models, but coverage is inconsistent.
Pricing Comparison
OIO by Korrus — A19
WiZ Connected — Tunable White A19
For a 10-bulb setup: OIO runs $299.99, WiZ runs $120–150. That's a $150–180 difference. The question is whether spectral engineering and clinical validation are worth that premium. For someone whose goal is better sleep and circadian health — the reason you're reading this page — the answer is yes.
The Pros and Cons
OIO by Korrus
Pros
- True spectral engineering (blue removed, not dimmed)
- 68% more melatonin (Salk Institute)
- 4 spectral modes, 1500K–6500K
- 500+ patents, Nobel laureate lineage
- Full smart home: Matter, Alexa, Google, Apple
- No hub required
Cons
- $30–35/bulb (2x–3x WiZ price)
- Not dimmer compatible
- Only sold at korrus.com
- 800 lumens (some WiZ models go higher)
WiZ Connected
Pros
- $12–15/bulb — excellent budget smart bulb
- No hub required
- Good app with scheduling
- Available everywhere
- Signify build quality
Cons
- Blue spike persists at all color temperatures
- "Circadian Rhythm" mode is just CCT scheduling
- No published circadian/melatonin data
- Warm range only to 2200K
- Inconsistent Matter support across models
The Verdict
WiZ is a great smart bulb. It's not a circadian bulb.
WiZ does a lot of things well at a very good price. If you want inexpensive smart lights you can voice-control and schedule, it's one of the best values in the category. Its "Circadian Rhythm" mode will make your lights shift from cool to warm throughout the day, which looks nice and feels natural.
But it won't change the spectral composition of the light hitting your retina. The blue spike is still there at every setting. Your ipRGCs still detect it. Your melatonin production is still affected. The label says "circadian," but the physics say "CCT scheduling."
OIO costs roughly 2x more per bulb and delivers a fundamentally different technology: spectral modes that physically remove blue wavelengths, clinically validated at the Salk Institute to produce 68% more melatonin. If circadian biology is why you're shopping, that's the product built for the job.
Bottom line: WiZ's circadian mode is a marketing feature. OIO's circadian modes are an engineering achievement. If you just want a cheap smart bulb, buy WiZ. If you want light that actually supports your circadian rhythm with clinical evidence behind it, OIO is the only option here.