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Should I upgrade my iMac (Retina 4K, 21.5-inch, Late 2015)?

11 years old · Not on the current macOS; endoflife.date lists Monterey security support as ended 16 September 2024

Quick look

Price
£1,1992launch price
Chip
Core i53.1GHz quad-core Intel
CPU
4-coreCPU
GPU
Not available3GPU
Memory
8GBmemory, base
Storage
1TBstorage, base
Display
21.5-inchdisplay
Released
13 October 20152Released
Security updates
16 September 20244Security updates ended

Each figure is from the source marked1 unless it carries its own number.

Software support

Security updates
Not available5
macOS
macOS Monterey, not the current macOSThe iMac (Retina 4K, 21.5-inch, Late 2015) is not on the current macOS (macOS 27 Golden Gate); the newest it runs is macOS Monterey. endoflife.date lists security support for Monterey as ended on 16 September 2024.

No newer Mac with a store price we hold

We hold no Apple UK store price for any Mac in the iMac 21.5-inch line, so this page names no newer Mac to set the iMac (Retina 4K, 21.5-inch, Late 2015) against. That is a gap in what we hold, not a statement about what Apple sells.

Specifications

Body

Dimensions
450 x 528 x 175 mm
Weight
5.68 kg
Ports
Two Thunderbolt 2 ports, four USB 3 ports, SDXC card slot, Gigabit Ethernet (RJ-45), 3.5 mm headphone jack
Thunderbolt ports
2
Thunderbolt version
Thunderbolt 2
USB-A ports
4
HDMI
No HDMI port.6
SD card slot
Yes
Headphone jack
Yes
Keyboard
Magic Keyboard
Touch ID
No Touch ID.6

Display

Display size
21.5 in
Resolution
4096 x 2304
Display type
Retina 4K display with IPS technology
Wide colour (P3)
Yes7

Chip and memory

Chip
3.1GHz quad-core Intel Core i5
Apple silicon
Intel processor, not Apple silicon.8
CPU cores
4
Graphics
Intel Iris Pro Graphics 6200
Chip options
3.1GHz quad-core Intel Core i5 or 3.3GHz quad-core Intel Core i7
Memory (base)
8GB
Memory (maximum)
16GB
Memory options
8GB or 16GB
Memory upgradeable by user
No, as Apple documents9
Storage (base)
1TB
Storage (maximum)
2TB
Storage options
1TB hard drive, 1TB or 2TB Fusion Drive, or 256GB or 512GB flash storage (SSD)10

Connectivity

Wi-Fi
802.11ac Wi-Fi
Bluetooth
4.0
Ethernet
10/100/1000BASE-T Gigabit Ethernet (RJ-45)
External displays (base)
1

Camera and audio

Camera
FaceTime HD camera
Speakers
Stereo speakers
Microphones
Dual microphones

Platform

Shipped with
OS X El Capitan11
Newest macOS
macOS Monterey12
Model identifier
iMac16,212
Part numbers
MK452xx/A13
Model year
2015

Benchmarks

Geekbench 7 (CPU, single-core)
1,08014
Geekbench 7 (CPU, multi-core)
3,12214

An iMac has no battery, so battery rows do not apply.

Software support

Feature updates until
Not available15
endoflife.date lists security support for Monterey as ended
16 September 20244
Basis
endoflife.date’s listed end of security support for Monterey16

Trade-in and used prices

No used or trade-in figures for the iMac (Retina 4K, 21.5-inch, Late 2015): we have not matched it to a CeX listing we can confirm is this exact Mac, and we would rather show nothing than a near miss.

More

Sources

  1. Apple Support (UK) — iMac (Retina 4K, 21.5-inch, Late 2015) - Technical Specification · Default for iMac (Retina 4K, 21.5-inch, Late 2015) · Apple’s figure · read 15 Sep 2026

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  2. Apple Newsroom (UK) — Apple Updates iMac Family with Stunning New Retina Displays · Apple’s figure · read 15 Sep 2026

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  3. Not published by Apple. Pages checked: Apple Support (UK) — iMac (Retina 4K, 21.5-inch, Late 2015) - Technical Specification; Apple Support (UK) — Identify your iMac model; Apple Newsroom (UK) — Apple Updates iMac Family with Stunning New Retina Displays. Read 9 Oct 2026

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  4. endoflife.date — Apple macOS · third-party figure · read 2 Oct 2026

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  5. Apple publishes no end date of its own; the date in the macOS row is endoflife.date’s record, not Apple’s. Checked: endoflife.date. Read 2 Oct 2026

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  6. No HDMI port. No Touch ID. Checked: Apple Support (UK) — iMac (Retina 4K, 21.5-inch, Late 2015) - Technical Specification. Read 9 Oct 2026

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  7. Apple Newsroom (UK) — Apple Updates iMac Family with Stunning New Retina Displays · Apple’s figure · read 3 Oct 2026

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  8. Intel processor, not Apple silicon. Checked: Apple Support (UK) — iMac (Retina 4K, 21.5-inch, Late 2015) - Technical Specification. Read 15 Sep 2026

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  9. Apple Support (UK) — Install memory in an iMac · Apple’s figure · read 18 Oct 2026

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  10. Apple Support (UK) — iMac (Retina 4K, 21.5-inch, Late 2015) - Technical Specification · Apple’s figure · read 11 Oct 2026

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  11. Apple Newsroom (UK) — Apple Updates iMac Family with Stunning New Retina Displays · Apple’s figure · read 9 Oct 2026

    ↩

  12. Apple Support (UK) — Identify your iMac model · Apple’s figure · read 15 Sep 2026

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  13. Apple Support (UK) — Identify your iMac model · Apple’s figure · read 18 Oct 2026

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  14. Geekbench Browser (Primate Labs) · third-party figure · read 11 Oct 2026

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  15. Feature updates: end date not published by Apple. Checked: endoflife.date. Read 2 Oct 2026

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  16. This is endoflife.date’s cycle end for Monterey, not necessarily the day of Apple’s last patch. The newest macOS Apple lists this Mac for is macOS Monterey. endoflife.date records security updates for Monterey as ended on 16 September 2024. Source: endoflife.date. Read 2 Oct 2026

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Not published by Apple

iMac (Retina 4K, 21.5-inch, Late 2015). Apple doesn’t publish for this Mac: colours, pixel density, brightness, refresh rate, nano-texture option, GPU cores, storage upgradeable by user, maximum continuous power. Geekbench 7 Metal: the Mac chart has no Metal score for this Mac (chart read 10 Oct 2026). Pages checked: Apple Support (UK) — iMac (Retina 4K, 21.5-inch, Late 2015) - Technical Specification; Apple Support (UK) — Identify your iMac model; Apple Newsroom (UK) — Apple Updates iMac Family with Stunning New Retina Displays, read 9 Oct 2026.

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