iMac (21.5-inch, 2017) vs iMac (21.5-inch, Late 2015)
Quick look
| Figure | iMac (21.5-inch, 2017)1 | iMac (21.5-inch, Late 2015)2 |
|---|---|---|
| Price | £1,0493launch price | £8994launch price |
| Chip | Core i52.3GHz dual-core Intel | Core i51.6GHz dual-core Intel |
| CPU | 2-coreCPU | 2-coreCPU |
| Memory | 8GBmemory, base | 8GBmemory, base |
| Storage | 1TBstorage, base | 1TBstorage, base |
| Display | 21.5-inchdisplay | 21.5-inchdisplay |
| Released | 7 June 20175ReleasedIn Apple Stores; orderable online from 5 June 2017. | 13 October 20154Released |
| Security updates | 15 September 20256Security updates ended | 16 September 20246Security updates ended |
- Price
- The iMac (21.5-inch, 2017) is £1,049 at launch, per Apple UK Store (archived 23 June 2017); the iMac (21.5-inch, Late 2015) is £899 at launch, per Apple Newsroom (UK).
True to scale
Front faces, from Apple’s published dimensions, drawn to one scale and superposed. Corner rounding is our drawing convention, not a measurement.
Specifications
Each figure is from the source marked by its Mac’s name unless it carries its own small number, which links to where that figure was read.
Body
| Specification | iMac (21.5-inch, 2017)1 | iMac (21.5-inch, Late 2015)2 |
|---|---|---|
| Dimensions | 450 x 528 x 175 mm | 450 x 528 x 175 mm |
| Weight | 5.44 kg | 5.68 kg |
| Ports | Two Thunderbolt 3 (USB-C) ports, four USB-A ports, SDXC card slot, Gigabit Ethernet (RJ-45), 3.5 mm headphone jack | Two Thunderbolt 2 ports, four USB 3 ports, SDXC card slot, Gigabit Ethernet (RJ-45), 3.5 mm headphone jack |
| Thunderbolt ports7 | 2 | 2 |
| Thunderbolt version | Thunderbolt 3 | Thunderbolt 2 |
| USB-A ports | 4 | 4 |
| HDMI | No HDMI port.8 | No HDMI port.9 |
| SD card slot | Yes | Yes |
| Headphone jack | Yes | Yes |
| Keyboard | Magic Keyboard | Magic Keyboard |
| Touch ID | No Touch ID.8 | No Touch ID.9 |
Display
| Specification | iMac (21.5-inch, 2017)1 | iMac (21.5-inch, Late 2015)2 |
|---|---|---|
| Display size | 21.5 in | 21.5 in |
| Resolution | 1920 x 1080 | 1920 x 1080 |
| Display type | LED-backlit display | LED-backlit display with IPS technology |
Chip and memory
| Specification | iMac (21.5-inch, 2017)1 | iMac (21.5-inch, Late 2015)2 |
|---|---|---|
| Chip | 2.3GHz dual-core Intel Core i5 | 1.6GHz dual-core Intel Core i5 |
| Apple silicon | Intel processor, not Apple silicon.10 | Intel processor, not Apple silicon.11 |
| CPU cores | 2 | 2 |
| Graphics | Intel Iris Plus Graphics 640 | Intel HD Graphics 6000 |
| Chip options | 2.3GHz dual-core Intel Core i5 | 1.6GHz dual-core Intel Core i5 or 2.8GHz quad-core Intel Core i5 |
| Memory (base) | 8GB | 8GB |
| Memory (maximum) | 16GB | 16GB |
| Memory options | 8GB or 16GB | 8GB or 16GB |
| Memory upgradeable by user | No, as Apple documents12 | No, as Apple documents12 |
| Storage (base) | 1TB | 1TB |
| Storage (maximum) | 1TB | 2TB |
| Storage options | 1TB hard drive, 1TB Fusion Drive or 256GB SSD | 1TB hard drive, 1TB or 2TB Fusion Drive, or 256GB flash storage (SSD) |
Connectivity
| Specification | iMac (21.5-inch, 2017)1 | iMac (21.5-inch, Late 2015)2 |
|---|---|---|
| Wi-Fi | 802.11ac Wi-Fi | 802.11ac Wi-Fi |
| Bluetooth | 4.2 | 4.0 |
| Ethernet | 10/100/1000BASE-T Gigabit Ethernet (RJ-45) | 10/100/1000BASE-T Gigabit Ethernet (RJ-45) |
| External displays (base) | 2 | 1 |
Sources
Apple Support (UK) — iMac (21.5-inch, 2017) - Technical Specifications ·
↩Apple Support (UK) — iMac (21.5-inch, Late 2015) - Technical Specification ·
↩- ↩
Apple Newsroom (UK) — Apple Updates iMac Family with Stunning New Retina Displays ·
↩- ↩
endoflife.date — Apple macOS ·
↩Different Thunderbolt generations. iMac (21.5-inch, 2017): Thunderbolt 3. iMac (21.5-inch, Late 2015): Thunderbolt 2.
↩iMac (21.5-inch, 2017): No HDMI port. No Touch ID.
↩iMac (21.5-inch, Late 2015): No HDMI port. No Touch ID.
↩iMac (21.5-inch, 2017): Intel processor, not Apple silicon.
↩iMac (21.5-inch, Late 2015): Intel processor, not Apple silicon.
↩Apple Support (UK) — Install memory in an iMac ·
↩Not published by Apple.
↩Apple Newsroom (UK) — Apple Updates iMac Family with Stunning New Retina Displays ·
↩Apple Support (UK) — Identify your iMac model ·
↩
Not published by Apple
iMac (21.5-inch, 2017). Apple doesn’t publish for this Mac: colours, pixel density, brightness, refresh rate, wide colour (P3), nano-texture option, GPU cores, storage upgradeable by user, maximum continuous power. Geekbench 7: the Mac chart has no entry for this Mac, so no figures are shown (chart read 10 Oct 2026). Pages checked: Apple Support (UK) — iMac (21.5-inch, 2017) - Technical Specifications; Apple Support (UK) — Identify your iMac model; Apple Newsroom (UK) — iMac receives major update featuring more powerful graphics, faster processors, Thunderbolt 3 and brighter displays, read 9 Oct 2026.
iMac (21.5-inch, Late 2015). Apple doesn’t publish for this Mac: colours, pixel density, brightness, refresh rate, wide colour (P3), nano-texture option, GPU cores, storage upgradeable by user, maximum continuous power. Geekbench 7: the Mac chart has no entry for this Mac, so no figures are shown (chart read 10 Oct 2026). Pages checked: Apple Support (UK) — iMac (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.
If you own one of them
Whether to move is a different question from which is better. Each Mac has a page on it: what its successor changes (the newest Mac in its line where Apple sells one, otherwise the Mac this site treats as its replacement, which can be in another line), what it fetches and whether it still gets updates. Should I upgrade my iMac (21.5-inch, 2017)? · Should I upgrade my iMac (21.5-inch, Late 2015)?
Other comparisons
The pairs a buyer of either Mac would also weigh. Any two Macs in the catalogue can be compared from the chooser.