Choosing between two of the most popular air purifiers on the market can be a challenge. Both the Levoit Core 300S and the Core 400S offer smart features, effective H13 HEPA filtration, and a sleek design, but they are built for different needs and spaces. One is a compact and capable unit for smaller rooms, while the other is a significant step up in power and efficiency.

This detailed comparison breaks down the key differences in performance, noise levels, long-term running costs, and smart features to help you decide which model offers the best value for your UK home. We'll look beyond the marketing and into the real-world performance to make your choice clear and simple.

(Disclosure: When you buy through links on our site, we may earn an affiliate commission at no extra cost to you. We recommend only products we believe in.)

 

Levoit 300S vs 400S: The Key Differences at a Glance

For those short on time, here is a direct comparison of the most important specifications. The Core 400S is not just a larger version of the 300S; it represents a substantial upgrade in almost every performance metric.

 

Core Differences Explained in Detail

While the comparison table gives a quick overview, the real story is in the details of the engineering and design. The Core 400S isn't just bigger; it's a more advanced machine that offers tangible benefits beyond its raw power.

 

Performance and Coverage: How Much More Power Do You Get?

The most significant difference between the two models is their raw cleaning power. The Core 400S boasts a Clean Air Delivery Rate (CADR) of up to 442 m³/h, which is nearly double the 240 m³/h offered by the Core 300S.

This translates directly to room size. The Core 300S is highly effective in smaller spaces like bedrooms and home offices up to 20 m². The Core 400S, however, can comfortably handle medium-to-large living rooms, open-plan areas, and master bedrooms up to 37 m², cleaning the air far more rapidly. In performance tests, the 400S was consistently faster at clearing smoke and demonstrated a higher particle removal efficiency.

 

Noise, Efficiency, and Design: Is Bigger Actually Better?

You might assume that a more powerful motor would be a louder one, but that isn't the case here. Counterintuitively, the Core 400S is the quieter machine at every fan speed except for its lowest 'Sleep Mode' setting. This points to a more advanced and better-optimised motor and fan design. For users who are sensitive to background hum, understanding the different noise profiles is key.

This superior engineering also means the 400S is more energy-efficient at comparable output levels. Aesthetically, both share the same minimalist, cylindrical design, but the scale is different. The 400S is noticeably larger and heavier (52 cm tall vs 36 cm for the 300S), so be sure to measure your intended space.

 

Smart Features and Controls: A Clear Upgrade

Both purifiers share Levoit's excellent VeSync smart app ecosystem, allowing for remote control, scheduling, and integration with Amazon Alexa and Google Assistant for voice commands. However, the Core 400S provides a significant upgrade for data-conscious users.

While the 300S features a simple colour-coded ring on its display to indicate air quality (blue for good, green for moderate, etc.), the 400S adds a real-time numerical PM2.5 display. This gives you a precise, granular reading of the fine particulate matter in your air, allowing you to see exactly how clean it is at a glance.

Filtration System: Similar Tech, Different Scale

At their core, both models use the same effective technology. They rely on a comprehensive three-stage system, centred around a high-efficiency [H13 HEPA filtration](Guide - air filter) stage that captures 99.97% of airborne particles like pollen, dust, and pet dander. This is supported by a pre-filter for larger debris and an activated carbon layer to tackle odours and VOCs.

The key physical difference is the size of the filter itself. The Core 400S uses a much larger, taller filter cartridge. This increased surface area is a primary reason for its higher CADR and, as we'll see next, its longer lifespan.

 

Long-Term Cost of Ownership

An air purifier is an ongoing investment, and filter replacement is the most significant long-term cost. Here, the Core 400S demonstrates its superior value proposition.

 

Filter Lifespan and Annual Costs

The smaller filter in the Core 300S requires replacement every 6-8 months, with [official filters on Amazon UK — AFFILIATE LINK | rel="sponsored nofollow"] costing around £30. This results in an annual running cost of approximately £45 to £60.

The larger, more substantial filter in the Core 400S is designed to last a full 12 months. While the initial cost of the [official filter on Amazon UK — AFFILIATE LINK | rel="sponsored nofollow"] is higher (around £90), this longer lifespan makes the annual cost directly comparable to, and often better than, its smaller sibling when you factor in the superior performance and convenience of a single yearly change.

 

Our Verdict: Which Levoit Should You Buy in 2025?

The choice between these two excellent purifiers comes down to your room size and budget. While the initial saving on the 300S is tempting, the 400S justifies its higher price with significant upgrades across the board.

 

Reasons to Choose the Levoit Core 300S

The Core 300S is a fantastic choice if:

• You have a small room: It's perfectly sized for bedrooms, nurseries, or home offices under 20 m².
• Your budget is tight: The lower initial purchase price makes it more accessible.
• Space is a premium: Its smaller, more compact footprint is easier to place in a crowded room.

For those in this bracket, it remains one of the best air purifiers under £150

[Check price for Levoit Core 300S on Amazon UK — AFFILIATE LINK | rel="sponsored nofollow"]

 

Reasons to Choose the Levoit Core 400S

 

The Core 400S is the clear winner and the better long-term investment for most people. You should choose it if:

• You have a medium-to-large room: Its power is ideal for living rooms, open-plan spaces, and master bedrooms up to 37 m².
• You value quiet performance: The more advanced motor is quieter at most operational speeds.
• You want better long-term value: The longer filter life and superior energy efficiency make it more economical over time.
• You appreciate detailed data: The numerical PM2.5 display provides precise, real-time air quality information.

It stands as a top contender in the category of [best air purifiers under £250](Best under £250 (premium)).

[Check price for Levoit Core 400S on Amazon UK — AFFILIATE LINK | rel="sponsored nofollow"]

 

Frequently Asked Questions

 

Is the Levoit 400S worth the extra £70?

Yes, for most users. The extra cost gets you nearly double the cleaning power, quieter operation, a longer filter lifespan, and a more informative display. It's a significant upgrade in performance and long-term value, not just a size increase.

 

Can I use the 400S in a small bedroom?

You can, but it would be overkill. The Core 300S is more than capable of handling smaller rooms and will save you money on the initial purchase.

 

How do I know when to change the filter?

Both models have a filter replacement indicator light on the control panel that will illuminate when the filter has reached the end of its lifespan. The VeSync app will also send you a notification.

 

Are third-party filters any good?

While more affordable third-party filters are available, we recommend using official Levoit replacement filters to guarantee performance, fit, and filtration efficiency. Using unofficial filters may void your warranty.

 

Internal Links Proposed

• [Guide - air filter](Guide - air filter)
• [Guide - noise](Guide - noise
• [Best under £150 ( standard)](Best under £150 ( standard))
• [Best under £250 (premium)](Best under £250 (premium))