← All iMac models

iMac M1

The M1 iMac runs local models at 68.25 GB/s of memory bandwidth with 8 to 16 GB of unified memory. On Apple Silicon that memory is shared with the GPU, so the whole pool is available for weights: at 16 GB you can hold roughly a 20B dense model at Q4. A base M chip is the narrow end of the memory bus. It runs small models pleasantly and stops hard at the memory ceiling, which is the constraint you will hit first.

Apple no longer sells this configuration new. It stays fully evaluated here because the used market is where most of its local AI value now sits.

By , Founder & Lead Engineer— Updated

Specifications

ChipApple M1
CPU cores8
GPU cores7 or 8
Unified memory8 or 16 GB
Memory bandwidth68.25 GB/s
Neural Engine11 TOPS
Released2020
AvailabilityUsed market

Memory bandwidth is faster than 0% of the Apple Silicon chips shipped in a Mac, against a 1228 GB/s peak.

Its memory ceiling is above 0% of them, against a 512 GB peak.

Pick your configuration

Every option Apple sells with this chip. The model list below recomputes against the one you pick.

GPU cores

Unified memory

What each memory option runs

Unified memory is the ceiling and it is soldered, so this is the decision you cannot revisit.

8 GB unified memory

7 GB usable for weights · 68.25 GB/s

4,997 of 6,563 models fit, and 3,331 of them run with headroom rather than as a squeeze.

Largest model at Q4
moondream3 preview · 9.27B
Best all-round pick
LFM2.5 230M · Q8_0 · ~155 tok/s

16 GB unified memory

14 GB usable for weights · 68.25 GB/s

5,572 of 6,563 models fit, and 5,054 of them run with headroom rather than as a squeeze.

Largest model at Q4
maple preview · 20.21B
Best all-round pick
LFM2.5 230M · Q8_0 · ~155 tok/s

What a 8 GB M1 iMac can run

Every model in the database against this exact configuration, at 68.25 GB/s. Ratings and speeds are the same numbers the model pages show.

Showing 6563 of 6563 models

General · Liquid AI · 2026-06-24

Q8_0Excellent
0.8 GB9% of RAM~155 tok/sEstimated0.23B params
Run with ToolPiper

General · Liquid AI · 2026-03-31

Q8_0Excellent
0.9 GB11% of RAM~102 tok/sEstimated0.35B params
Run with ToolPiper

General · cagrigungor · 2026-08-06

Q8_0Excellent
0.8 GB10% of RAM~132 tok/sEstimated0.27B params
Run with ToolPiper

Multimodal · Alibaba · 2026-02-28

Q8_0Excellent
1.5 GB18% of RAM~41 tok/sEstimated0.87B params
Run with ToolPiper

General · openbmb · 2026-05-21

Q8_0Excellent
1.7 GB21% of RAM~33 tok/sEstimated1.08B params
Run with ToolPiper

Multimodal · Alibaba · 2026-02-28

Q8_0Excellent
1.5 GB18% of RAM~41 tok/sEstimated0.87B params
Run with ToolPiper

Reasoning · openonerec · 2026-06-09

Q8_0Excellent
1.4 GB17% of RAM~45 tok/sEstimated0.8B params
Run with ToolPiper

General · ktruestory · 2026-05-28

Q8_0Excellent
1.7 GB21% of RAM~33 tok/sEstimated1.08B params
Run with ToolPiper

General · Liquid AI · 2025-10-28

Q8_0Excellent
0.9 GB11% of RAM~102 tok/sEstimated0.35B params
Run with ToolPiper

General · frontiersmind · 2026-08-03

Q8_0Excellent
1.2 GB15% of RAM~55 tok/sEstimated0.65B params
Run with ToolPiper

Multimodal · Liquid AI · 2025-08-12

Q8_0Excellent
1.0 GB13% of RAM~79 tok/sEstimated0.45B params
Run with ToolPiper

General · Liquid AI · 2026-01-20

Q8_0Excellent
1.8 GB23% of RAM~31 tok/sEstimated1.17B params
Run with ToolPiper

General · Liquid AI · 2025-09-30

Q8_0Excellent
0.9 GB11% of RAM~102 tok/sEstimated0.35B params
Run with ToolPiper

General · Liquid AI · 2025-09-03

Q8_0Excellent
0.9 GB11% of RAM~102 tok/sEstimated0.35B params
Run with ToolPiper

General · Liquid AI · 2025-08-25

Q8_0Excellent
0.9 GB11% of RAM~102 tok/sEstimated0.35B params
Run with ToolPiper

General · Liquid AI · 2025-09-03

Q8_0Excellent
0.9 GB11% of RAM~102 tok/sEstimated0.35B params
Run with ToolPiper

General · petrouil · 2026-07-23

Q8_0Excellent
3.4 GB43% of RAMBenchmark needed2.61B params
Run with ToolPiper

General · Liquid AI · 2026-01-05

Q8_0Excellent
1.8 GB23% of RAM~31 tok/sEstimated1.17B params
Run with ToolPiper

General · Liquid AI · 2025-07-10

Q8_0Excellent
0.9 GB11% of RAM~102 tok/sEstimated0.35B params
Run with ToolPiper

General · Liquid AI · 2026-01-04

Q8_0Excellent
1.8 GB23% of RAM~31 tok/sEstimated1.17B params
Run with ToolPiper

Chat · Liquid AI · 2026-01-06

Q8_0Excellent
1.8 GB23% of RAM~31 tok/sEstimated1.17B params
Run with ToolPiper

General · ibm-granite · 2025-10-07

Q8_0Excellent
0.9 GB11% of RAM~102 tok/sEstimated0.35B params
Run with ToolPiper

General · Liquid AI · 2025-07-10

Q8_0Excellent
1.3 GB17% of RAM~48 tok/sEstimated0.74B params
Run with ToolPiper

General · viorikaai-org · 2026-07-05

Q8_0Excellent
0.6 GB7% of RAM~715 tok/sEstimated0.05B params
Run with ToolPiper

General · bananamind · 2026-07-17

Q8_0Excellent
0.5 GB6% of RAM~3,575 tok/sEstimated0.01B params
Run with ToolPiper

General · maliosdark · 2026-07-09

Q8_0Excellent
0.6 GB7% of RAM~715 tok/sEstimated0.05B params
Run with ToolPiper

General · raidium · 2026-06-15

Q8_0Excellent
0.5 GB7% of RAM~1,788 tok/sEstimated0.02B params
Run with ToolPiper

Embedding · taide · 2026-06-12

Q8_0Excellent
0.8 GB10% of RAM~119 tok/sEstimated0.3B params
Run with ToolPiper

Multimodal · datalab-to

Q8_0Excellent
1.3 GB16% of RAM~52 tok/sEstimated0.69B params
Run with ToolPiper

General · Alibaba · 2025-04-28

Q8_0Excellent
1.2 GB15% of RAM~60 tok/sEstimated0.6B params
Run with ToolPiper

General · distil-labs

Q8_0Excellent
0.9 GB11% of RAM~102 tok/sEstimated0.35B params
Run with ToolPiper

General · Alibaba · 2025-09-23

Q8_0Excellent
1.3 GB17% of RAM~48 tok/sEstimated0.75B params
Run with ToolPiper

General · Liquid AI · 2025-07-10

Q8_0Excellent
1.8 GB23% of RAM~31 tok/sEstimated1.17B params
Run with ToolPiper

Multimodal · Liquid AI · 2026-01-05

Q8_0Excellent
2.3 GB29% of RAM~22 tok/sEstimated1.6B params
Run with ToolPiper

Multimodal · Liquid AI

Q8_0Excellent
1.0 GB13% of RAM~79 tok/sEstimated0.45B params
Run with ToolPiper

General · Liquid AI

Q8_0Excellent
0.9 GB11% of RAM~102 tok/sEstimated0.35B params
Run with ToolPiper

General · onnx-community · 2025-04-28

Q8_0Excellent
1.0 GB13% of RAM~79 tok/sEstimated0.45B params
Run with ToolPiper

General · baidu

Q8_0Excellent
0.9 GB11% of RAM~99 tok/sEstimated0.36B params
Run with ToolPiper

General · openbmb · 2025-06-05

Q8_0Excellent
1.0 GB12% of RAM~83 tok/sEstimated0.43B params
Run with ToolPiper

General · farbodtavakkoli

Q8_0Excellent
2.5 GB31% of RAMBenchmark needed1.77B params
Run with ToolPiper

General · kamilamila

Q8_0Excellent
1.2 GB15% of RAM~58 tok/sEstimated0.62B params
Run with ToolPiper

General · ordenwills

Q8_0Excellent
0.9 GB11% of RAM~102 tok/sEstimated0.35B params
Run with ToolPiper

General · Microsoft

Q8_0Excellent
0.7 GB9% of RAMBenchmark needed0.17B params
Run with ToolPiper

General · Microsoft

Q8_0Excellent
0.7 GB9% of RAMBenchmark needed0.17B params
Run with ToolPiper

General · tencent

Q8_0Excellent
1.1 GB14% of RAM~66 tok/sEstimated0.54B params
Run with ToolPiper

General · primeintellect

Q8_0Excellent
1.1 GB14% of RAMBenchmark needed0.54B params
Run with ToolPiper

General · Liquid AI · 2025-08-22

Q8_0Excellent
1.8 GB23% of RAM~31 tok/sEstimated1.17B params
Run with ToolPiper

General · Liquid AI · 2025-09-03

Q8_0Excellent
1.8 GB23% of RAM~31 tok/sEstimated1.17B params
Run with ToolPiper

General · Liquid AI · 2025-09-03

Q8_0Excellent
1.8 GB23% of RAM~31 tok/sEstimated1.17B params
Run with ToolPiper

General · darthcrawl · 2026-05-07

Q8_0Excellent
0.5 GB7% of RAM~894 tok/sEstimated0.04B params
Run with ToolPiper

General · appvoid

Q8_0Excellent
0.6 GB8% of RAM~397 tok/sEstimated0.09B params
Run with ToolPiper

General · pinkstack

Q8_0Excellent
0.9 GB11% of RAM~102 tok/sEstimated0.35B params
Run with ToolPiper

Coding · Liquid AI

Q8_0Excellent
0.9 GB11% of RAM~102 tok/sEstimated0.35B params
Run with ToolPiper

General · squ11z1

Q8_0Excellent
0.9 GB11% of RAM~102 tok/sEstimated0.35B params
Run with ToolPiper

General · iselabvn

Q8_0Excellent
0.9 GB11% of RAM~102 tok/sEstimated0.35B params
Run with ToolPiper

General · meddies

Q8_0Excellent
0.9 GB11% of RAM~102 tok/sEstimated0.35B params
Run with ToolPiper

General · mihaipopa-1

Q8_0Excellent
0.9 GB11% of RAM~102 tok/sEstimated0.35B params
Run with ToolPiper

General · lazos

Q8_0Excellent
0.9 GB11% of RAM~102 tok/sEstimated0.35B params
Run with ToolPiper

General · q1ngmang

Q8_0Excellent
0.9 GB11% of RAM~102 tok/sEstimated0.35B params
Run with ToolPiper

General · baidu

Q8_0Excellent
0.9 GB11% of RAM~99 tok/sEstimated0.36B params
Run with ToolPiper

Multimodal · Liquid AI

Q8_0Excellent
1.0 GB13% of RAM~79 tok/sEstimated0.45B params
Run with ToolPiper
Q8_0Excellent
1.2 GB15% of RAM~58 tok/sEstimated0.62B params
Run with ToolPiper

Reasoning · supralabs

Q8_0Excellent
1.3 GB17% of RAM~48 tok/sEstimated0.75B params
Run with ToolPiper

General · kylesayrs

Q8_0Excellent
1.4 GB17% of RAMBenchmark needed0.8B params
Run with ToolPiper

General · inference-optimization

Q8_0Excellent
1.4 GB18% of RAMBenchmark needed0.85B params
Run with ToolPiper

General · Alibaba · 2025-04-27

Q8_0Excellent
1.3 GB17% of RAM~48 tok/sEstimated0.75B params
Run with ToolPiper

General · Alibaba · 2024-05-31

Q8_0Excellent
1.0 GB13% of RAM~73 tok/sEstimated0.49B params
Run with ToolPiper

General · hmellor · 2025-07-22

Q8_0Excellent
1.9 GB24% of RAM~29 tok/sEstimated1.24B params
Run with ToolPiper

Multimodal · tencent

Q8_0Excellent
1.7 GB22% of RAMBenchmark needed1.12B params
Run with ToolPiper

Multimodal · ath-maas

Q8_0Excellent
1.4 GB18% of RAM~42 tok/sEstimated0.85B params
Run with ToolPiper

General · Google · 2022-03-02

Q8_0Excellent
0.5 GB6% of RAM~3,575 tok/sEstimated0.01B params
Run with ToolPiper

Multimodal · paddlepaddle

Q8_0Excellent
1.6 GB20% of RAM~37 tok/sEstimated0.96B params
Run with ToolPiper

General · stefanruseti · 2025-06-04

Q8_0Excellent
1.9 GB24% of RAM~29 tok/sEstimated1.24B params
Run with ToolPiper

Multimodal · paddlepaddle

Q8_0Excellent
1.6 GB20% of RAM~37 tok/sEstimated0.96B params
Run with ToolPiper

General · etherll

Q8_0Excellent
1.3 GB17% of RAM~48 tok/sEstimated0.74B params
Run with ToolPiper

Multimodal · paddlepaddle

Q8_0Excellent
1.6 GB20% of RAM~37 tok/sEstimated0.96B params
Run with ToolPiper
Q8_0Excellent
1.5 GB18% of RAM~41 tok/sEstimated0.87B params
Run with ToolPiper

Coding · rahul7star

Q8_0Excellent
1.5 GB18% of RAM~41 tok/sEstimated0.87B params
Run with ToolPiper

General · limloop

Q8_0Excellent
0.6 GB7% of RAM~715 tok/sEstimated0.05B params
Run with ToolPiper

General · melikegks

Q8_0Excellent
1.3 GB17% of RAM~48 tok/sEstimated0.75B params
Run with ToolPiper
Q8_0Excellent
1.3 GB17% of RAM~48 tok/sEstimated0.75B params
Run with ToolPiper

General · iselabvn

Q8_0Excellent
1.3 GB17% of RAM~48 tok/sEstimated0.75B params
Run with ToolPiper

Multimodal · 8f-ai

Q8_0Excellent
1.3 GB17% of RAM~48 tok/sEstimated0.75B params
Run with ToolPiper

General · cooperdk

Q8_0Excellent
1.4 GB18% of RAM~42 tok/sEstimated0.85B params
Run with ToolPiper

Multimodal · dingdust

Q8_0Excellent
1.4 GB18% of RAM~42 tok/sEstimated0.85B params
Run with ToolPiper

Multimodal · yuandaxia

Q8_0Excellent
1.4 GB18% of RAM~42 tok/sEstimated0.85B params
Run with ToolPiper

Reasoning · healshsj

Q8_0Excellent
1.7 GB21% of RAM~33 tok/sEstimated1.08B params
Run with ToolPiper

Multimodal · inclusionai

Q8_0Excellent
1.7 GB22% of RAM~32 tok/sEstimated1.11B params
Run with ToolPiper

Multimodal · Alibaba · 2026-02-28

Q8_0Excellent
3.0 GB38% of RAM~16 tok/sEstimated2.27B params
Run with ToolPiper

Multimodal · Alibaba · 2026-02-28

Q8_0Excellent
3.0 GB38% of RAM~16 tok/sEstimated2.27B params
Run with ToolPiper

General · Microsoft

Q8_0Excellent
0.8 GB10% of RAM~132 tok/sEstimated0.27B params
Run with ToolPiper

General · Microsoft

Q8_0Excellent
1.2 GB15% of RAM~60 tok/sEstimated0.6B params
Run with ToolPiper

General · farbodtavakkoli

Q8_0Excellent
1.0 GB13% of RAM~79 tok/sEstimated0.45B params
Run with ToolPiper

General · voyageai

Q8_0Excellent
0.9 GB11% of RAM~102 tok/sEstimated0.35B params
Run with ToolPiper

General · farbodtavakkoli

Q8_0Excellent
0.8 GB10% of RAM~132 tok/sEstimated0.27B params
Run with ToolPiper

General · TII · 2025-05-01

Q8_0Excellent
1.1 GB14% of RAM~69 tok/sEstimated0.52B params
Run with ToolPiper

General · jakobhuss

Q8_0Excellent
0.8 GB10% of RAM~132 tok/sEstimated0.27B params
Run with ToolPiper

General · sapientinc · 2026-05-17

Q8_0Excellent
1.8 GB23% of RAM~30 tok/sEstimated1.18B params
Run with ToolPiper

Coding · shahriarferdoush

Q8_0Excellent
1.9 GB24% of RAM~29 tok/sEstimated1.24B params
Run with ToolPiper

General · Liquid AI

Q8_0Excellent
1.8 GB23% of RAM~31 tok/sEstimated1.17B params
Run with ToolPiper

General · openbmb

Q8_0Excellent
1.7 GB21% of RAM~33 tok/sEstimated1.08B params
Run with ToolPiper

General · mesolitica

Q8_0Excellent
1.2 GB15% of RAM~57 tok/sEstimated0.63B params
Run with ToolPiper

General · benjamin

Q8_0Excellent
1.7 GB21% of RAM~33 tok/sEstimated1.07B params
Run with ToolPiper

Multimodal · Liquid AI · 2025-08-12

Q8_0Excellent
2.3 GB28% of RAM~23 tok/sEstimated1.58B params
Run with ToolPiper

General · numind

Q8_0Excellent
1.0 GB13% of RAM~78 tok/sEstimated0.46B params
Run with ToolPiper

General · divelab

Q8_0Excellent
1.2 GB15% of RAM~60 tok/sEstimated0.6B params
Run with ToolPiper

General · toxicityprompts

Q8_0Excellent
1.0 GB13% of RAM~73 tok/sEstimated0.49B params
Run with ToolPiper

General · lgai-exaone · 2025-07-11

Q8_0Excellent
1.9 GB24% of RAM~28 tok/sEstimated1.28B params
Run with ToolPiper

General · ibm-granite

Q8_0Excellent
0.9 GB11% of RAM~102 tok/sEstimated0.35B params
Run with ToolPiper
Q8_0Excellent
1.7 GB21% of RAM~33 tok/sEstimated1.08B params
Run with ToolPiper
Q8_0Excellent
1.2 GB15% of RAM~60 tok/sEstimated0.6B params
Run with ToolPiper

General · lmms-lab

Q8_0Excellent
1.1 GB13% of RAM~72 tok/sEstimated0.5B params
Run with ToolPiper

General · tabularisai

Q8_0Excellent
0.9 GB12% of RAM~94 tok/sEstimated0.38B params
Run with ToolPiper

General · numind

Q8_0Excellent
1.0 GB13% of RAM~73 tok/sEstimated0.49B params
Run with ToolPiper

General · isotonic

Q8_0Excellent
1.3 GB16% of RAMBenchmark needed0.7B params
Run with ToolPiper

General · manycore-research

Q8_0Excellent
1.2 GB15% of RAM~60 tok/sEstimated0.6B params
Run with ToolPiper

General · bezzam

Q8_0Excellent
1.4 GB17% of RAM~46 tok/sEstimated0.78B params
Run with ToolPiper

General · ibm-granite

Q8_0Excellent
4.2 GB52% of RAMBenchmark needed3.3B params
Run with ToolPiper

General · huihui-ai

Q8_0Excellent
1.5 GB18% of RAMBenchmark needed0.86B params
Run with ToolPiper

General · skis-ai-research

Q8_0Excellent
1.8 GB23% of RAM~31 tok/sEstimated1.17B params
Run with ToolPiper

General · thkim0305

Q8_0Excellent
1.6 GB20% of RAM~36 tok/sEstimated1B params
Run with ToolPiper
1.1 GB13% of RAM~72 tok/sEstimated0.5B params
Run with ToolPiper
1.1 GB13% of RAM~72 tok/sEstimated0.5B params
Run with ToolPiper
1.1 GB13% of RAM~72 tok/sEstimated0.5B params
Run with ToolPiper

General · lunahr

Q8_0Excellent
1.2 GB15% of RAM~60 tok/sEstimated0.6B params
Run with ToolPiper

General · ibm-granite

Q8_0Excellent
0.9 GB11% of RAM~105 tok/sEstimated0.34B params
Run with ToolPiper
1.1 GB13% of RAM~72 tok/sEstimated0.5B params
Run with ToolPiper

General · lunahr

Q8_0Excellent
1.2 GB15% of RAM~60 tok/sEstimated0.6B params
Run with ToolPiper
1.1 GB13% of RAM~72 tok/sEstimated0.5B params
Run with ToolPiper
1.1 GB13% of RAM~72 tok/sEstimated0.5B params
Run with ToolPiper

General · acon96

Q8_0Excellent
0.8 GB10% of RAM~132 tok/sEstimated0.27B params
Run with ToolPiper

General · reaperdoesntknow

Q8_0Excellent
1.6 GB20% of RAM~35 tok/sEstimated1.01B params
Run with ToolPiper

General · kerzgrr

Q8_0Excellent
0.8 GB10% of RAM~132 tok/sEstimated0.27B params
Run with ToolPiper

General · kerzgrr

Q8_0Excellent
0.8 GB10% of RAM~132 tok/sEstimated0.27B params
Run with ToolPiper

General · gokaygokay

Q8_0Excellent
0.8 GB10% of RAM~132 tok/sEstimated0.27B params
Run with ToolPiper

General · litert-community

Q8_0Excellent
0.8 GB10% of RAM~132 tok/sEstimated0.27B params
Run with ToolPiper

General · rishiraj

Q8_0Excellent
0.8 GB10% of RAM~132 tok/sEstimated0.27B params
Run with ToolPiper

General · multiversecomputingcai

Q8_0Excellent
0.8 GB10% of RAM~123 tok/sEstimated0.29B params
Run with ToolPiper

General · ibm-granite

Q8_0Excellent
0.9 GB11% of RAM~105 tok/sEstimated0.34B params
Run with ToolPiper

General · etherll

Q8_0Excellent
0.9 GB11% of RAM~105 tok/sEstimated0.34B params
Run with ToolPiper

General · reallexi

Q8_0Excellent
1.0 GB13% of RAM~73 tok/sEstimated0.49B params
Run with ToolPiper

General · n99av80n

Q8_0Excellent
1.0 GB13% of RAM~73 tok/sEstimated0.49B params
Run with ToolPiper

General · reallexi

Q8_0Excellent
1.0 GB13% of RAM~73 tok/sEstimated0.49B params
Run with ToolPiper
Q8_0Excellent
1.2 GB15% of RAM~60 tok/sEstimated0.6B params
Run with ToolPiper

General · hamoai

Q8_0Excellent
1.2 GB15% of RAM~60 tok/sEstimated0.6B params
Run with ToolPiper

General · quipuai

Q8_0Excellent
1.2 GB15% of RAM~60 tok/sEstimated0.6B params
Run with ToolPiper

General · occ-ai

Q8_0Excellent
1.2 GB15% of RAM~60 tok/sEstimated0.6B params
Run with ToolPiper

General · p-e-w

Q8_0Excellent
1.2 GB15% of RAM~60 tok/sEstimated0.6B params
Run with ToolPiper

General · kulpreetkaurs

Q8_0Excellent
1.2 GB15% of RAM~60 tok/sEstimated0.6B params
Run with ToolPiper

General · dingdust

Q8_0Excellent
1.7 GB21% of RAM~33 tok/sEstimated1.08B params
Run with ToolPiper

7-core vs 8-core GPU

Both bins run the same 68.25 GB/s memory bus, so token generation is the same on either one. The extra cores show up in image and video work, not in tokens per second.

ConfigurationMemory bandwidthMemory optionsModels that fit
8-core CPU, 7-core GPU68.25 GB/s8, 16 GBIdentical
8-core CPU, 8-core GPU68.25 GB/s8, 16 GBIdentical

Measured on the M1

Nobody has submitted a benchmark on the M1 yet, so every speed on this page is the formula estimate rather than a measured run. The estimate is bandwidth-driven and calibrated against chips that do have data, which makes it a good guide and not a promise.

ToolPiper contributes a result anonymously when you run the benchmark, and the leaderboard shows every chip that already has one.

What comes next

Projection dated 2026-09-08

Apple has not announced any of this. The M7 Max and Ultra are the first parts Apple designed after cancelling a generation to reach them, so extrapolating from the M5 under-represents them. These rows assume LPDDR6, whose wider channels grow every bus by half, at its top speed bin by the time the Max and Ultra ship. The 1.5 TB Ultra ceiling is Bloomberg's reported design target, and whether that configuration ships depends on the memory market. Stacked memory or a new package fabric would land above these numbers; nobody outside Apple can price that yet.

M6Projected

Shipping chip, not yet in this Mac · expected 2026

153 to 170 GB/s · 16 to 32 GB unified memory

12-core CPU · 12-core GPU · 76 TOPS Neural Engine

Would hold about a 42B model at Q4

M7Projected

Projected chip · expected 2027

240 GB/s · 16 to 48 GB unified memory

12-core CPU · 12 or 16-core GPU · 76 TOPS Neural Engine

Would hold about a 63B model at Q4

Why unified memory is the number that matters

On a PC the model has to fit in GPU VRAM, which is a separate pool from system RAM and usually the smaller of the two. Apple Silicon has one pool. The M1's 68.25 GB/s bus is shared by CPU, GPU, and Neural Engine, so a 16 GB machine can hand almost all of that to a model with no copy across a bus.

Apple stopped selling this one, which is exactly why it is interesting. The iMac takes base M chips only, so unified memory is the number that decides what you can run on it. A used M1 at 16 GB still gives you 68.25 GB/s and a hard 20B ceiling, and neither number degrades with age the way a battery does.

Common questions

Can the M1 iMac run a 70B model?

No. A 70B model at Q4_K_M needs about 46 GB, and the largest M1 iMac tops out at 16 GB, which leaves about 14 GB for weights. The practical ceiling on this machine is around 20B parameters at Q4.

How much unified memory should I get with the M1 iMac?

Memory is the only spec that changes what you can run at all. 8 GB holds about a 9B model at Q4; 16 GB holds about 20B. It is soldered, so this is a one-time decision, and it is the upgrade worth paying for before core count.

How fast are local LLMs on the M1?

Token generation is bandwidth-bound, so M1 throughput scales with its 68.25 GB/s memory bus. Divide bandwidth by the size of the weights actually read per token to get the ceiling, then expect roughly half of that in practice. A 7B model at Q4 reads about 4 GB per token pass, so the M1 lands in the tens of tokens per second and a 70B model lands in the single digits.

Is the 8-core GPU worth it over the 7-core on the M1?

Not for LLMs. Both bins run the same 68.25 GB/s memory bus and take the same memory options, and token generation is bound by bandwidth rather than GPU cores. The extra cores show up in image generation and video work, not in tokens per second.

Is a used M1 iMac still worth buying for local AI?

For inference, the specs that matter do not age: 68.25 GB/s and up to 16 GB of unified memory are the same numbers today as they were in 2020. A used M1 at the top memory option usually beats a new base-tier machine at the same price on both. Check the battery and the display, not the silicon.

Run these models on your iMac

ToolPiper downloads, manages, and runs local models on Apple Silicon. Free, and nothing leaves the machine.