M1 vs. M3 iMac Buyer's Guide: 15+ Differences Compared

The iMac now features the M3 chip, replacing the M1 model that Apple introduced in April 2021, so how different are the two successive generations?

M1 versus M3 iMac Feature 1
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 2021 ‌iMac‌ has now been discontinued by Apple and prices at third-party resellers are falling. As such, some customers may be weighing up whether to upgrade to a 2021 or 2023 ‌iMac‌.

The two Apple silicon ‌iMac‌ models share the overwhelming majority of their features, so should you consider buying or sticking with the first-generation to save money? This breakdown also serves as a way to see all the differences that the 2023 ‌iMac‌ brings to the table.

‌iMac‌ (2021) ‌iMac‌ (2023)
‌M1‌ chip (5nm/N5) M3 chip (3nm/N3B)
3.20 GHz CPU clock speed 4.05 GHz CPU clock speed
7- or 8-core GPU 8- or 10-core GPU
New GPU architecture
Dynamic Caching
Hardware-accelerated ray tracing
Hardware-accelerated mesh shading
Video decode engine Higher-bandwidth video decode engine
Hardware-accelerated H.264 and HEVC Hardware-accelerated H.264, HEVC, ProRes, and ProRes RAW
ProRes encode and decode engine
Support for AV1 decode
Neural engine 60% faster Neural engine
Image signal processor (ISP) "New" image signal processor (ISP)
3.5mm headphone jack 3.5mm headphone jack with support for high-impedance headphones
Wi-Fi 6 Wi-Fi 6E
Bluetooth 5.0 Bluetooth 5.3
68.25GB/s memory bandwidth 100GB/s memory bandwidth
8GB or 16GB unified memory 8GB, 16GB, or 24GB unified memory

Overall, the 2023 ‌iMac‌ is a very minor upgrade over the 2021 model, with the M3 chip being the most significant change. As a result, it is difficult to recommend upgrading from an ‌M1‌ model unless you specifically need better performance, hardware-accelerated graphics, or a larger quantity of memory. The new ‌iMac‌ is up to 2x faster than the prior generation with the ‌M1‌ chip, according to Apple, meaning that it should deliver a considerable performance improvement for those who need it.

Most users of the ‌M1‌ ‌iMac‌ will not be able to justify upgrading to the M3 ‌iMac‌, but customers coming from an older Intel-based machine or those who do not have one at all could still have good reason to prefer the latest model. For those upgrading from an Intel-based ‌‌iMac‌‌, Apple says that the new ‌‌iMac‌‌ is up to 2.5x faster than previous 27-inch models and 4.5x faster than previous 21.5-inch models.

The 2023 ‌iMac‌ is otherwise very similar to the 2021 model, so some customers who have very basic needs and are interested in buying an ‌iMac‌ may prefer to look for a discounted 2021 model. The ‌iMac‌ is priced starting at $1,299, so if you are not interested in its new features and can find the original model for substantially less, it may be worth getting that instead. Even so, it should be remembered that this is a much older model; the M3 model will be more future-proof and capable in the long term.

Related Roundup: iMac
Buyer's Guide: iMac (Neutral)
Related Forum: iMac

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Top Rated Comments

Dharma-P Avatar
10 months ago
This iMac is an absolute joke.


* Terrible design with white bezels and pastel colors
* Odd screen size with only 60Hz and no local dimming/HDR support
* 8GB RAM in almost 2024?!
* 256GB base storage in almost 2024?!
* Accessories still have a Lightning port
* Very minor upgrade in a few years time where only the chip changed
* And despite all of the above, a starting price of EUR 1,560 (USD 1,660) in Europe.
Score: 37 Votes (Like | Disagree)
Warped9 Avatar
10 months ago
The haters are out in force.

There was nothing broken about the 24 iMac except in the minds of the haters. And now it’s 20% faster with added attributes and it hasn’t gone up in price. How dare they!

Looks like a win to me. I still want to see some real world reviews, but it looks very likely I’ll be ordering one to replace my 2011 21.5 Hakintosh. I’m thinking blue, 24GB RAM and 512GB-1TB SSD. My 3D modelling should run pretty good on that.
Score: 26 Votes (Like | Disagree)
dugbug Avatar
10 months ago

This iMac is an absolute joke.


* Terrible design with white bezels and pastel colors
* Odd screen size with only 60Hz and no local dimming/HDR support
* 8GB RAM in almost 2024?!
* 256GB base storage in almost 2024?!
* Accessories still have a Lightning port
* Very minor upgrade in a few years time where only the chip changed
* And despite all of the above, a starting price of EUR 1,560 (USD 1,660) in Europe.

Hardly a terrible design, but that is opinion based. You don't like it thats cool.

However this line:
"very minor upgrade! Only one chip changed!"

Dude. That one chip is the entire system.
Score: 25 Votes (Like | Disagree)
johnnytravels Avatar
10 months ago

This iMac is an absolute joke.


* Terrible design with white bezels
* Odd screen size with only 60Hz and no local dimming/HDR support
* 8GB RAM in almost 2024?!
* 256GB base storage in almost 2024?!
* Accessories still have a Lightning port
* Very minor upgrade in a few years time where only the chip changed
* And despite all of the above, a starting price of EUR 1,560 (USD 1,660) in Europe.

Yeah it's the iPad 10th generation of desktop computers. The nickel-and-diming that Cook does has almost become unbearable...
Score: 22 Votes (Like | Disagree)
T'hain Esh Kelch Avatar
10 months ago

Get rid of the chin already
Unlikely I would say. The chin of the iMac is one os its unique aspects, that makes it immediately recognizable. And the hardware needs to go somewhere, so it is either a chin, or a fatter iMac.
Score: 16 Votes (Like | Disagree)
johnnytravels Avatar
10 months ago
Watching the Scary Fast video comparing the M3 to the M1 to make it seem more powerful than it is, I almost believe that Apple didn't upgrade the iMac to the M2 so that they’d have some plausibility making that comparison.
Score: 14 Votes (Like | Disagree)