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Apple / unified

Apple M1 Ultra

128 GB decides what fits. 800 GB/s decides how fast it runs once it does.

Computed for 128 GB, the largest configuration. The Apple M1 Ultra is also sold with 64 GB, and what fits changes with it.

Run it with 64 GB →

Open in the calculator →Best models for 128 GB, on every card that size →

Quick answer
The Apple M1 Ultra fits 248 of 320 sized models entirely in its 128 GB; the largest widely used one is Qwen3.8-Flash-Next (111.6 GB at Q4_K_M). Memory decides what fits; its 800 GB/s of bandwidth decides how fast it answers.

At 8,192 tokens of context with the whole model in device memory. Speeds are estimates from memory bandwidth, not benchmarks run on this card.

Apple M1 Ultra · 128 GB · 800 GB/s · Q4_K_M where published · 8,192 tokensSpecificationpublished dataDecode speedestimate

248 of 320 fit entirely

248 of the 320 models the engine can size fit entirely in device memory at Q4_K_M where it is published, otherwise the nearest published format, and 8,192 tokens. Unified memory is one pool, so there is no second memory tier to spill into; the remaining 72 do not run at this context.

78%of the models the engine can size fit entirely
128GB of device memory
800GB/s memory bandwidth
0run with system memory
72do not run at 8,192 tokens

Featured models · Q4_K_M at 8,192 tokens, including offload

ModelNeedsVerdictDecodeCalculator
Qwen3.5-2B2.3B parameters2.32 GBfits~136 tok/sOpen →
NVIDIA-Nemotron-3-Nano-4B-BF164.0B parameters3.46 GBfits~108 tok/sOpen →
Qwen3-VL-8B-Instruct8.8B parameters7.04 GBfits~74 tok/sOpen →
Qwen3.5-9B9.7B parameters7.05 GBfits~82 tok/sOpen →
gemma-4-12B-it12B parameters9.54 GBfits~60 tok/sOpen →
gpt-oss-20b21B parameters13.8 GBfits~111 tok/sOpen →
Qwen3.8-27B28B parameters18.6 GBfits~39 tok/sOpen →
Qwen3.6-27B28B parameters18.6 GBfits~39 tok/sOpen →
Kimi-Linear-48B-A3B-Instruct49B parameters30.4 GBfits~122 tok/sOpen →
Qwen3.8-Flash-Next180B parameters111.6 GBfits~95 tok/sOpen →
DeepSeek-V4-Flash-Vision-Exp305B parameters188.1 GBshort by 60.1 GBdoes not runOpen →
GLM-5.3-Flash321B parameters198.3 GBshort by 70.3 GBdoes not runOpen →

These examples are selected from prominent labs using the catalogue’s latest Hugging Face 30-day downloads and repository-creation freshness signal, with newer releases guaranteed a place. Offloaded rows assume 32 GB of system RAM, and a speed is only shown for a row that runs. Fitting in memory is not the same as loading: whether the runtime and version you have supports each architecture and format on this machine has not been tested here. Each “Open” link carries the same model, format, context and RAM into the calculator.

Fits entirely in Apple M1 Ultra (128 GB) memory — 248 of 320 sized models

Every model that fitswhole model resident · offload off

The most demanding model that fits is Step-3.5-Flash at Q4_K_M: 127.0 GB of the 128 GB, leaving 1.03 GB spare.

Fully resident at 8,192 tokens (or the model’s own maximum, where that is shorter), offload off, at 800 GB/s. Each row is a run of the engine for this configuration; the rows start with current, prominent releases and “fits” is memory, not a tested runtime. Older or less prominent models remain available through this search and “Show all”.

Showing 40 of 248 models that fit.

ModelFormatNeedsSpareDecodeDownloads / 30dCalculator
Qwen3.8-27BQwen · 28B paramsQ4_K_M18.6 GB109.4 GB~39 tok/s6.9MOpen →
Qwen3.8-Flash-NextNEWQwen · 180B paramsQ4_K_M111.6 GB16.4 GB~95 tok/s1.4MOpen →
gemma-4-26B-A4B-itGoogle · 26B paramsQ4_K_M16.8 GB111.2 GB~108 tok/s13MOpen →
gemma-4-31B-itGoogle · 31B paramsQ4_K_M22.2 GB105.8 GB~30 tok/s9.9MOpen →
Qwen3.5-9BQwen · 9.7B paramsQ4_K_M7.05 GB121.0 GB~82 tok/s9MOpen →
Qwen3.5-4BQwen · 4.7B paramsQ4_K_M3.98 GB124.0 GB~108 tok/s7.8MOpen →
Qwen3.6-35B-A3BQwen · 36B paramsQ4_K_M23.1 GB104.9 GB~123 tok/s3.3MOpen →
gemma-4-12B-itGoogle · 12B paramsQ4_K_M9.54 GB118.5 GB~60 tok/s1.9MOpen →
Qwen3.6-27BQwen · 28B paramsQ4_K_M18.6 GB109.4 GB~39 tok/s2.5MOpen →
Qwen3.5-2BQwen · 2.3B paramsQ4_K_M2.32 GB125.7 GB~136 tok/s4.9MOpen →
gemma-4-E4B-itGoogle · 8.0B paramsQ4_K_M5.86 GB122.1 GB~103 tok/s4.4MOpen →
NVIDIA-Nemotron-3.5-Lightning-30B-A3B-BF16NVIDIA · 32B paramsQ4_K_M20.3 GB107.7 GB~32 tok/s530KOpen →
NVIDIA-Nemotron-3-Nano-4B-BF16NVIDIA · 4.0B paramsQ4_K_M3.46 GB124.5 GB~108 tok/s3.4MOpen →
gemma-4-E2B-itGoogle · 5.1B paramsQ4_K_M4.02 GB124.0 GB~139 tok/s3MOpen →
Qwen3.5-0.8BQwen · 873M paramsQ4_K_M1.46 GB126.5 GB~155 tok/s2.6MOpen →
Qwen3-VL-8B-InstructQwen · 8.8B paramsQ4_K_M7.04 GB121.0 GB~74 tok/s14.6MOpen →
Qwen3.5-27BQwen · 28B paramsQ4_K_M18.6 GB109.4 GB~39 tok/s1.9MOpen →
North-Micro-Vision-InstructCohereLabs · 2.5B paramsQ4_K_M2.99 GB125.0 GB~122 tok/s180.7KOpen →
Qwen3.5-35B-A3BQwen · 36B paramsQ4_K_M23.1 GB104.9 GB~123 tok/s1.6MOpen →
NVIDIA-Nemotron-3-Super-120B-A12B-BF16NVIDIA · 124B paramsQ4_K_M76.9 GB51.1 GB~9.3 tok/sSlow1.2MOpen →
granite-4.2-8bIBM · 8.8B paramsQ4_K_M7.49 GB120.5 GB~70 tok/s128.4KOpen →
GLM-4.7-Flashzai-org · 31B paramsQ4_K_M20.4 GB107.6 GB~31 tok/s1.8MOpen →
granite-4.1-3bIBM · 3.4B paramsQ4_K_M3.72 GB124.3 GB~107 tok/s521.8KOpen →
LFM2.5-2.6BLiquidAI · 2.7B paramsQ4_K_M2.61 GB125.4 GB~125 tok/s108.1KOpen →
Qwen3-VL-4B-InstructQwen · 4.4B paramsQ4_K_M4.72 GB123.3 GB~94 tok/s3.5MOpen →
granite-4.1-30bIBM · 29B paramsQ4_K_M20.4 GB107.6 GB~31 tok/s301.5KOpen →
Qwen3.5-122B-A10BQwen · 125B paramsQ4_K_M77.9 GB50.1 GB~80 tok/s512.6KOpen →
Qwen3-VL-2B-InstructQwen · 2.1B paramsQ4_K_M3.05 GB125.0 GB~119 tok/s2.8MOpen →
granite-4.2-3bIBM · 3.7B paramsQ4_K_M3.72 GB124.3 GB~107 tok/s50.6KOpen →
LFM2.5-230MLiquidAI · 230M paramsQ4_K_M1.05 GB126.9 GB~166 tok/s88.6KOpen →
Qwen3-0.6BQwen · 752M paramsQ4_K_M2.22 GB125.8 GB~134 tok/s29.7MOpen →
Qwen3-Coder-NextQwen · 80B paramsQ4_K_M50.0 GB78.0 GB~106 tok/s596.3KOpen →
gpt-oss-20bOpenAI · 21B paramsQ4_K_M13.8 GB114.2 GB~111 tok/s6.6MOpen →
granite-4.2-30bIBM · 29B paramsQ4_K_M20.7 GB107.3 GB~31 tok/s35.8KOpen →
granite-4.1-8bIBM · 8.8B paramsQ4_K_M7.49 GB120.5 GB~70 tok/s179.3KOpen →
NVIDIA-Nemotron-3-Nano-30B-A3B-BF16NVIDIA · 32B paramsQ4_K_M20.3 GB107.7 GB~32 tok/s875.2KOpen →
gpt-oss-120bOpenAI · 117B paramsQ4_K_M71.9 GB56.1 GB~96 tok/s4.5MOpen →
LFM2.5-VL-3BLiquidAI · 3.1B paramsQ4_K_M2.85 GB125.1 GB~125 tok/s26.7KOpen →
MiMo-V2.6-Distill-Qwen-9BNEWXiaomiMiMo · 9.4B paramsQ4_K_M6.90 GB121.1 GB~82 tok/s14.6KOpen →
Qwen3-4B-Instruct-2507Qwen · 4.0B paramsQ4_K_M4.72 GB123.3 GB~94 tok/s3.7MOpen →

Sized at the format most people actually download, not at FP16. The catalogue ordered by downloads →

The Apple M1 Ultra, model by model

Under the hood

The specification behind every figure

What the manufacturer publishes for this device, and the pages it was read from.

Manufacturer specification

Memory scopeunified-system
Capacity128 GB
Published options64 GB, 128 GB
Bandwidth800 GB/s
Memory typeunified memory
Bus widthNot published
FP32 peakNot published
Dense matrix peakNot published without sparsity
PowerNot published

Source ledger

Apple unveils M1 Ultra ↗
Retrieved 2026-08-31

Caveats

  • Capacity and bandwidth are the maxima Apple publishes for this chip; lower configurations exist and run slower. No VRAM capacity is claimed, and the operating system's own use is not subtracted.
  • Apple publishes no peak throughput figure for this chip, so no compute roof is priced for it and time to first token is withheld.

Published capacity is a hardware ceiling, not guaranteed free runtime memory. The calculator shows the runtime reserve separately rather than folding it into a single number.

Run the diagnostic on the Apple M1 Ultra →
llmbottleneck
catalogue 2026-10-03models 327devices 135