The successor is the better mouse. Whether it is better enough depends on a $30 gap that will not stay still.
This is an independent, research-based review. It draws on Logitech’s published specifications and on independent testing and reviews from RTINGS, Tom’s Hardware and TechRadar, along with owner reports from user forums. The mouse was not personally tested, and Logitech had no involvement.
Now that the MX Master 4 has been on sale for a while, the question about its predecessor has shifted from whether it is good to whether it is still the smart buy. As of September 2026, Logitech’s US store lists the MX Master 3S Bluetooth edition at about $89.99, down from $99.99, and the MX Master 4 at about $119.99. That $30 gap will not stay fixed, so check both prices before deciding.
The short answer: the 3S is still a very capable desk mouse, and at that discount it is the better value for most buyers who want what this line has always done well. The Master 4 is the more complete product, but its additions are refinements rather than a reinvention, and their worth depends on whether you would actually use them.
What the 3S still gets right
The MX Master’s appeal has never been its sensor. It is about taking the friction out of repetitive desk work, and that has not changed.
The centerpiece is the MagSpeed scroll wheel, which is electromagnetic rather than mechanical. It ticks through lines in ratchet mode for precision and releases into a free spin when flicked, so a 200-page PDF or a long spreadsheet stops being a chore. Logitech quotes up to 1,000 lines per second; the exact figure matters less than the ability to move quickly through long documents and still land where you meant to. Tom’s Hardware found the wheel genuinely useful across documents, web pages, spreadsheets and multi-monitor work.
The thumb wheel is the other half of that story. It scrolls horizontally by default, which matters in wide spreadsheets, video timelines and design canvases, and it can be reassigned to zoom, volume, tab switching or other functions through Logi Options+. That software is where the mouse earns its price: buttons and wheels can behave differently in Excel than in Chrome or Photoshop, and Tom’s Hardware found this per-application customization one of the product’s real strengths.
Multi-device use rounds it out. The 3S pairs with up to three devices over Bluetooth, or Logi Bolt on versions that include the receiver, and Logitech Flow lets the cursor move between compatible Windows and macOS computers. For anyone running a work laptop beside a personal desktop, that removes a small annoyance many times a day.
Battery life is rated by Logitech at up to 70 days per charge under its qualifying conditions, with quick-charge claims for supported versions. Treat that as a ceiling rather than a promise; even a fraction of it makes charging an afterthought.
The specs that look bigger than they are
The 8,000 DPI sensor is the headline number and largely beside the point. High sensitivity can help when pushing a cursor across a very high-resolution display or several monitors, but it does not make anyone faster at work. Tom’s Hardware’s reviewer did not need anything near the maximum on a multi-monitor setup and settled on a lower value. The more useful sensor detail is that Logitech says it tracks on glass at least about 4 mm thick, a real convenience on a glass desk and irrelevant otherwise.
Quiet Clicks are a similar case. Logitech’s “90% less click noise” figure is its own comparison with the previous MX Master 3, not an independent measurement, and volume is only half the story. Tom’s Hardware described the feel of the softer switches as something buyers may or may not like, a subjective difference rather than a clear upgrade. If you share an office, quieter is welcome; if you like a crisp click, try one before committing.
Where it genuinely falls short
The 3S is a big mouse. Logitech lists it at around 141 g, RTINGS measured 141.2 g, and RTINGS describes it as large and bulky and notes it can be less suitable for smaller hands. That shape is the point for people who want a supported, palm-filling grip at a desk. It works against you if you have small hands, prefer a fingertip grip, are used to lightweight mice or want something to carry around. It is also right-handed only.
Some controls have drawn criticism. Tom’s Hardware found the device-switch button on the underside inconvenient, which slightly undercuts the multi-device pitch, and described the thumb-area button as less natural than the rest of the layout.
It is not a gaming mouse. RTINGS rates it highly for office and productivity work but not for competitive gaming, where its weight and its latency and polling behavior set it apart from purpose-built alternatives.
On longevity, some owners have reported erratic scroll-wheel behavior, which RTINGS has acknowledged in its review history, and others describe the coating wearing or turning sticky after long use. These are user reports rather than test results; weigh them against the warranty and return policy, but they do not make the 3S a risky purchase.
What the MX Master 4 actually changed
The Master 4 keeps the fundamentals: the MagSpeed wheel, the thumb wheel, three-device pairing and the broad right-handed shape. On top of those it adds haptic feedback and what Logitech calls the Actions Ring, an on-screen shortcut menu opened by pressing a new haptic panel under the thumb. Logitech makes efficiency claims for that feature based on its own study; treat them as the manufacturer’s numbers. The controls have been revised, the shell uses different materials, and there are connectivity and design refinements.
There is a cost beyond price. Independent testing put the Master 4 at roughly 151–152 g, heavier than a mouse that was already heavy. RTINGS has suggested the new materials should hold up better over time than the 3S coating, which is plausible, but the Master 4 has not existed long enough for anyone to know.
RTINGS’ direct comparison lands where you would expect: the Master 4 is the more fully featured mouse, and the 3S remains attractive when discounted. TechRadar has made the same argument. The question is how large the discount needs to be.
Who should buy which
Buy the MX Master 3S if you work mainly at a desk, are right-handed with medium-to-large hands, live in documents, spreadsheets and browser tabs, switch between two or three machines, and would not use haptic feedback or a shortcut ring if you had them. At a $30 gap it delivers nearly all the everyday value of the line for a quarter less money.
Buy the MX Master 4 if the haptics and Actions Ring appeal to you, since those are the real additions, or if the price difference shrinks to a few dollars, at which point the newer design is hard to pass up. It is also the more defensible choice if you plan to keep the mouse for many years and would rather bet on the newer shell, provided you accept that the bet is not yet proven.
Buy something else if you have small hands, are left-handed, need a travel mouse, prefer a light fingertip-style mouse or want one mouse for work and serious gaming. Neither MX Master is built for you, and no discount changes that.
Verdict
The MX Master 3S is no longer the most advanced productivity mouse Logitech makes, but nearly everything that made it worth buying is still here: the scroll wheel, the horizontal wheel, the per-app customization and the multi-device switching. The Master 4 mainly adds and refines features rather than changing the core MX Master workflow, and its main additions are ones many buyers will not miss. As long as the 3S sells for meaningfully less, and roughly $30 qualifies, it is the stronger-value pick for a desk-bound, right-handed workflow. If that gap closes, the Master 4 becomes the easy answer.
Sources
Logitech
- MX Master 3S Bluetooth Edition (product page)
- Specification: MX Master 3S Bluetooth Edition (support)
- Getting Started: MX Master 3S (support)
- MX Master 4 (product page)
- Getting Started: MX Master 4 (support)
- Actions Ring in Logitech Options+
Independent reviews and testing
- RTINGS: Logitech MX Master 3S Review
- RTINGS: Logitech MX Master 4 Review
- RTINGS: Logitech MX Master 3S vs MX Master 4
- Tom’s Hardware: Logitech MX Master 3S Mouse Review: King of Wireless Productivity
- TechRadar, Nico Arboleda (June 2026): I love Logitech’s MX Master 4 mouse, but the older MX Master 3S is the better buy
Owner reports
- Public user forums, used only as anecdotal context for the scroll-wheel and coating remarks
Prices are Logitech US store listings checked in September 2026 and change often. Manufacturer claims, independent test findings and owner reports are attributed as such throughout.