M1 vs. M3 vs. M4 iMac Buyer's Guide: 25+ Upgrades Compared

Monday, October 28, 2024 5:52 PM

Apple's third Apple silicon iMac gains the M4 chip alongside a range of other small but notable improvements, so how does the new machine compare to its two predecessors?

M4 iMac Feature Teal
The 2021 ‌iMac‌ was the first of its kind to feature an Apple silicon chip, replacing previous Intel-based models with 21.5- and 27-inch displays. It offered an all-new ultra-thin design, a 24-inch Retina display, a six-speaker system with force-cancelling woofers, and an array of seven two-tone color options. The 2023 model was a minor update that added the M3 chip and specification updates like Bluetooth 5.3 and Wi-Fi 6E. One year later, the latest, M4 version of the device looks like a much more substantial upgrade, offering a dramatically more powerful Neural Engine, 16GB of memory as standard, a 12-megapixel camera with Center Stage, USB-C accessories, and a nano-texture display option.

The 2021 and 2023 iMacs have now been discontinued by Apple and prices at third-party resellers are falling. As such, some customers may be weighing up whether to pick up a 2021 or 2023 ‌iMac‌ instead of the latest model, while some existing ‌iMac‌ users may be wondering if it's now time to upgrade to the M4 model.

The three Apple silicon ‌iMac‌ models share the overwhelming majority of their features, so should you consider buying or sticking with the first- or second-generation models to save money? This breakdown also serves as a way to see all the differences that the 2024 ‌iMac‌ brings to the table.


‌iMac‌ (2021)‌iMac‌ (2023)‌iMac‌ (2024)
M1 chip (made with TSMC's 5nm (N5) process)M3 chip (made with TSMC's 3nm (N3) process)M4 chip (made with TSMC's enhanced ‌3nm‌ (N3E) process)
3.20 GHz maximum CPU clock speed4.05 GHz maximum CPU clock speed4.30 GHz maximum CPU clock speed
16 billion transistors25 billion transistors28 billion transistors
8-core CPU8- or 10-core CPU8- or 10-core CPU
7- or 8-core GPU8- or 10-core GPU8- or 10-core GPU

Updated GPU architectureUpdated GPU architecture with improved efficiency

Dynamic CachingDynamic Caching

Hardware-accelerated ray tracingHardware-accelerated ray tracing

Hardware-accelerated mesh shadingHardware-accelerated mesh shading
Video decode engineHigher-bandwidth video decode engineHigher-bandwidth video decode engine
Hardware-accelerated H.264 and HEVCHardware-accelerated H.264, HEVC, ProRes, and ProRes RAWHardware-accelerated H.264, HEVC, ProRes, and ProRes RAW

ProRes encode and decode engineProRes encode and decode engine

Support for AV1 decodeSupport for AV1 decode
LPDDR4X memory LPDDR5 memoryLPDDR5X memory
68.25GB/s memory bandwidth100GB/s memory bandwidth120GB/s memory bandwidth
8GB or 16GB unified memory8GB, 16GB, or 24GB unified memory16GB, 24GB, or 32GB unified memory
16-core Neural Engine, 11 trillion operations per second16-core Neural Engine, 18 trillion operations per second16-core Neural Engine, 38 trillion operations per second
1080p FaceTime HD camera1080p ‌FaceTime‌ HD camera12-megapixel camera


Center Stage with support for Desk View
Image signal processor (ISP)"New" image signal processor (ISP)"New" image signal processor (ISP)


Nano-texture display option


Dedicated display engine
3.5mm headphone jack3.5mm headphone jack with support for high-impedance headphones3.5mm headphone jack with support for high-impedance headphones
Up to two Thunderbolt/USB 4 ports and two USB 3 portsUp to two Thunderbolt/USB 4 ports and two USB 3 portsUp to four Thunderbolt 4 ports
Wi-Fi 6Wi-Fi 6EWi-Fi 6E
Bluetooth 5.0Bluetooth 5.3Bluetooth 5.3
Available in Silver, Green, Yellow, Orange, Pink, Purple, and BlueAvailable in Silver, Green, Yellow, Orange, Pink, Purple, and BlueAvailable in Silver, as well as new shades of Green, Yellow, Orange, Pink, Purple, and Blue
Magic Keyboard and Magic Mouse/Magic Trackpad with Lightning portMagic Keyboard and Magic Mouse/Magic Trackpad with Lightning portMagic Keyboard and Magic Mouse/Magic Trackpad with USB-C port




The 2024 ‌iMac‌ with the M4 chip marks a much more substantial upgrade compared to the 2021 and 2023 models. Key improvements such as the significantly more powerful Neural Engine for AI and machine learning tasks, increased standard memory of 16GB, 12-megapixel camera with Center Stage, and support for USB-C accessories make it an appealing choice for future-proofing. Performance-wise, it delivers a meaningful boost, especially for those upgrading from the ‌M1‌ ‌iMac‌ or older Intel-based iMacs, where Apple claims up to 6x faster performance than the most popular Intel ‌iMac‌. 

For ‌M1‌ ‌iMac‌ users, the M4 model could be worth considering if they require enhanced performance or a richer set of features, such as hardware-accelerated ray tracing, nano-texture display option, or simply a better webcam. However, M3 ‌iMac‌ users may find fewer incentives to upgrade, as the performance gap between M3 and M4 is good but not as significant in daily use unless the system is pushed to the limit. The M3 ‌iMac‌ is built to handle demanding tasks and will remain relevant for several more years, but ‌M1‌ ‌iMac‌ users may want to begin considering an upgrade. 

Starting at $1,299, the new ‌iMac‌ remains a solid investment for those looking for a device with longevity, a robust array of features, and meaningful upgrades over the original ‌M1‌ model or older Intel machines. However, if you have basic needs and find a discounted 2023 ‌iMac‌, this could still offer good value, though the M4 will better meet the needs of those seeking higher performance, better features, and a more forward-looking setup.