What Makes Gemma 4 Different

Gemma 4 is not an incremental update. Three architectural innovations set it apart from every previous Google open model and most of its competitors.

First, the Per-Layer Embeddings (PLE) technique used in the E2B and E4B variants. Instead of sharing a single embedding table across all layers, PLE assigns specialized embeddings at each transformer layer. This squeezes significantly more capability out of small parameter counts, which is why the 4B-effective E4B punches well above its weight class on reasoning benchmarks.

Second, the Mixture-of-Experts (MoE) architecture in the 26B-A4B variant. With 128 experts and only 3.8 billion parameters active per token, this model delivers 26B-class knowledge with the speed and memory footprint of a 4B model. It is the densest expert configuration in any open-weight model to date.

Third, the Apache 2.0 license. Previous Gemma releases used a custom license with commercial restrictions. Gemma 4 drops all of that. You can use, modify, fine-tune, and redistribute every variant with no usage caps or monthly active user limits.

Multimodal by default: All four Gemma 4 variants accept text and image input natively. The E2B and E4B models also support audio input, making them the smallest multimodal models you can run locally on a Mac.

Which Gemma 4 Model Should You Run?

According to LLMCheck testing, the right Gemma 4 variant depends entirely on your hardware and workload. Here is how they compare:

Variant Architecture RAM (INT4) tok/s (M5 Max) Modality Best For
E2B 2.3B active, PLE ~1.5 GB ~155 Text + Image + Audio Edge, mobile, autocomplete
E4B 4B effective, PLE ~3 GB ~125 Text + Image + Audio General assistant, daily driver
26B-A4B MoE, 128 experts, 3.8B active ~18 GB ~48 Text + Image Reasoning, coding, agents
31B Dense 31B dense ~20 GB ~24 Text + Image Frontier quality, Arena #3

For most Mac users with 8-16 GB of RAM, the E4B is the sweet spot. It delivers strong general reasoning and multimodal capability at 125 tok/s while consuming just 3 GB of memory. If you have 32 GB or more, the 26B-A4B MoE variant offers a massive quality jump for only 18 GB of RAM, thanks to activating just 3.8B parameters per token.

Step-by-Step Setup with Ollama

Getting any Gemma 4 variant running on your Mac takes under three minutes. Ollama handles weight downloads, Metal GPU acceleration, and memory allocation automatically.

1. Install Ollama

Download from ollama.com or install via Homebrew:

brew install ollama

2. Start the Ollama server

ollama serve

3. Pull and run your chosen Gemma 4 variant

# Default E4B (recommended for most users)
ollama run gemma4

# Ultra-light E2B
ollama run gemma4:e2b

# MoE powerhouse (needs 18+ GB RAM)
ollama run gemma4:26b

# Dense flagship (needs 20+ GB RAM)
ollama run gemma4:31b

Ollama downloads the quantized weights automatically. The E4B is roughly a 2 GB download and launches in seconds. The 26B and 31B variants are larger (10-12 GB) and take a few minutes on typical broadband.

4. Verify Metal GPU acceleration

Open Activity Monitor and check that the ollama_llama_server process shows GPU usage. On Apple Silicon, Metal acceleration is enabled by default. If GPU reads 0%, restart with:

OLLAMA_METAL=1 ollama serve

Pro tip: Gemma 4 supports 256K context natively. To unlock extended context, set OLLAMA_NUM_CTX=131072 before launching. This allocates additional memory for 128K tokens of context.

Benchmark Results

According to LLMCheck testing across Apple Silicon configurations, here is how Gemma 4 stacks up against the current top local models:

Model Active Params Context RAM (INT4) tok/s (M5 Max) Arena ELO
Gemma 4 31B Dense 31B 256K ~20 GB ~24 1452 (#3)
Gemma 4 26B-A4B 3.8B 256K ~18 GB ~48 1441 (#6)
Gemma 4 E4B 4B 256K ~3 GB ~125
Qwen 3.5 9B 9B 262K ~6 GB ~78
Phi-4 Mini (3.8B) 3.8B 128K ~2.5 GB ~140

The standout result is the 26B-A4B MoE variant. It activates only 3.8B parameters per token yet ranks #6 on Arena AI with an ELO of 1441, outperforming many dense models five to ten times its active size. The 31B Dense variant at Arena #3 competes directly with closed-source APIs while running entirely on your Mac.

MLX vs Ollama: Which Runner?

Gemma 4 launched with day-one MLX support, giving Mac users two excellent options for local inference. According to LLMCheck analysis, the choice comes down to your workflow:

For raw speed on Apple Silicon, MLX has a slight edge. For convenience and ecosystem support, Ollama wins. Both are free and open source.

Best Use Cases for Gemma 4 on Mac

The breadth of the Gemma 4 family means there is a variant for nearly every local AI workflow: