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Llama 3.1 8B: Local Deployment Guide

Short answer: Llama 3.1 8B runs locally with ollama run llama3.1:8b. That pulls the Q4_K_M build, a 4.9 GB download, so an 8 GB GPU is the practical floor and 12 GB is comfortable. The 128K context window is real, but filling it costs about 17 GB of KV cache on top of the weights, which is why almost nobody runs it at 128K on a consumer card. Every figure on this page is from Meta’s model card, the model’s configuration file, or the file sizes published on Ollama and Hugging Face; this site has not benchmarked the model.

Meta's Llama 3.1 8B is the smallest model in the July 2024 release, and it keeps the 128K context window, tool calling and eight supported languages of its larger siblings. The default Ollama build is 4.9 GB (Q4_K_M), which is what makes it one of the most accessible open-weight models to run locally. It is one of the most accessible LLMs you can run locally; if you are still choosing a card, start with the AI hardware guide.

Released 2024-07-23•Last updated 2026-10-15

How much VRAM does Llama 3.1 8B need?

About 7 GB at Q4_K_M with an 8K context, so an 8 GB GPU is the floor: a 4.9 GB file, 1.1 GB of context cache and roughly 1 GB of buffers. A 12 GB card covers Q8_0 or a 32K context; 16 GB of system RAM is the equivalent floor without a GPU; the unquantised fp16 build needs a 24 GB card. The arithmetic is parameters × bits per weight ÷ 8: 8.03B × 4.90 bits ÷ 8 = 4.92 GB at Q4_K_M, which matches the published file.

weights (GB) ≈ parameters (billions) × bits per weight ÷ 8

Q4_K_M: 8.03 × 4.90 ÷ 8 ≈ 4.92 GB  ·  Q8_0: 8.03 × 8.5 ÷ 8 ≈ 8.5 GB  ·  fp16: 8.03 × 16 ÷ 8 ≈ 16.1 GB

Q4_K_M is not exactly 4 bits per weight: the k-quant format keeps some tensors at higher precision, which is why the published 4.92 GB file works out to 4.90 bits per weight rather than 4.

File sizes are from bartowski/Meta-Llama-3.1-8B-Instruct-GGUF and Ollama’s tag list. The context cache is arithmetic from the model’s config.json: 32 layers × 8 key-value heads × 128 dimensions, stored twice at 2 bytes, is 128 KB per token, or 1.07 GB for 8,192 tokens. “Memory needed” is file + that cache + a 1 GB allowance for buffers.

QuantisationFileOllama tag (listed size)Memory needed (8K context)Fits
Q2_K3.18 GB8b-instruct-q2_K (3.2GB)~5.3 GB6 GB card, with heavy quality loss
Q3_K_M4.02 GB8b-instruct-q3_K_M (4.0GB)~6.1 GB8 GB card
Q4_K_S4.69 GB8b-instruct-q4_K_S (4.7GB)~6.8 GB8 GB card
Q4_K_M4.92 GBllama3.1:8b (4.9GB) — the default~7.0 GB8 GB card
Q5_K_M5.73 GB8b-instruct-q5_K_M (5.7GB)~7.8 GB8 GB card, with little to spare
Q6_K6.60 GB8b-instruct-q6_K (6.6GB)~8.7 GB12 GB card
Q8_08.54 GB8b-instruct-q8_0 (8.5GB)~10.6 GB12 GB card
fp1616.07 GB8b-instruct-fp16 (16GB)~18.1 GB24 GB card
  • System RAM, no GPU: the file loads into RAM instead, so the same totals apply. 16 GB of RAM covers every build up to Q8_0 with room for the operating system; on an 8 GB machine only the Q2_K and Q3 builds leave enough free. See running an LLM on CPU only.
  • Mac: unified memory follows the same arithmetic; an 8 GB Mac is the same squeeze as an 8 GB machine with no GPU, and a 16 GB Mac is comfortable. See running Llama 3 on a Mac.
  • Disk: the download size in the table, once per build you pull.
  • The 128K window: the table assumes 8K of context. The next section shows what the full window adds.

For the wider ladder across model sizes see the 8 GB RAM model guide, best LLM for 8 GB of VRAM, best LLM for 12 GB of VRAM and the Ollama RAM and VRAM table.

Llama 3.1 8B size in GB: every Ollama tag

The default llama3.1:8b is 4.9 GB. Ollama carries fifteen instruct builds of the 8B model, from 3.2 GB at Q2_K to 16 GB at fp16, all with the 128K context. The sizes below are copied from the tag list; the 8b-text-* tags are the same ladder for the base (pretrained) model, and the 70B and 405B tags are on the Llama 3.1 70B and Llama 3.1 405B pages.

Ollama tagDownloadQuantisationNote
llama3.1:8b4.9GBQ4_K_Msame file as llama3.1:latest and llama3.1:8b-instruct-q4_K_M
llama3.1:8b-instruct-q2_K3.2GBQ2_K
llama3.1:8b-instruct-q3_K_S3.7GBQ3_K_S
llama3.1:8b-instruct-q3_K_M4.0GBQ3_K_M
llama3.1:8b-instruct-q3_K_L4.3GBQ3_K_L
llama3.1:8b-instruct-q4_04.7GBq4_0the older 4-bit format that llama3:8b also uses
llama3.1:8b-instruct-q4_K_S4.7GBQ4_K_S
llama3.1:8b-instruct-q4_15.1GBq4_1
llama3.1:8b-instruct-q5_05.6GBq5_0
llama3.1:8b-instruct-q5_K_S5.6GBQ5_K_S
llama3.1:8b-instruct-q5_K_M5.7GBQ5_K_M
llama3.1:8b-instruct-q5_16.1GBq5_1
llama3.1:8b-instruct-q6_K6.6GBQ6_K
llama3.1:8b-instruct-q8_08.5GBQ8_0
llama3.1:8b-instruct-fp1616GBfp16unquantised

Note the 4.7 GB vs 4.9 GB difference between llama3:8b and llama3.1:8b: both models have the same 8,030,261,248 parameters, but the Llama 3 default tag is the older q4_0 format while the Llama 3.1 default is Q4_K_M. The build names are explained in quantization explained.

What does the 128K context window actually cost?

About 17 GB of KV cache at the full 131,072 tokens, on top of the 4.9 GB of weights, so a 24 GB card is the floor for the whole window. This is the number missing from most Llama 3.1 8B write-ups. The weights are only half the memory bill; the cache grows linearly with how many tokens are in the window:

KV bytes/token = 2 (K and V) × layers × KV heads × head dim × bytes per value

= 2 × 32 × 8 × 128 × 2 (f16) = 131,072 bytes = 128 KB per token

Layer count, key-value head count and head dimension are from the published Llama 3.1 8B configuration (32 layers, 8 key-value heads under grouped-query attention, head dimension 128). This is arithmetic, not a measurement.

Context in useKV cache (f16)Total with the 4.9 GB Q4_K_M fileFits
4,096 tokens (Ollama default)0.54 GB~6.5 GB8 GB
8,192 tokens1.07 GB~7.0 GB8 GB
32,768 tokens4.3 GB~10.2 GB12 GB
65,536 tokens8.6 GB~14.5 GB16 GB
131,072 tokens (full window)17.2 GB~23.1 GB24 GB

So the honest version of “128K context on an 8 GB card” is: the model supports it, your GPU does not. Ollama’s documentation says it uses a 4,096-token window by default, so you also do not get the long window unless you ask for it: /set parameter num_ctx 32768 inside ollama run, OLLAMA_CONTEXT_LENGTH=32768 ollama serve, or num_ctx in an API request. Quantising the cache to 8-bit roughly halves the figures above, at some cost to long-context recall.

How fast will Llama 3.1 8B run on my hardware?

We have measured this model on our own Apple M3 Pro and on a rented NVIDIA L4 (the tables further down); for any other card or Mac, what you can do before buying anything is compute the ceiling. Token generation on a local LLM is bandwidth-bound: to emit one token the runtime streams every weight it is using out of memory, so:

ceiling (tokens/sec) = memory bandwidth (GB/s) ÷ model size in memory (GB)

at Q4_K_M: your card’s published bandwidth ÷ 4.92 GB

This is an upper bound, not a prediction. Real output lands well below it: the formula ignores attention over the KV cache, prompt processing, sampling, and the fact that no runtime reaches 100% of a vendor’s peak bandwidth figure. Take the bandwidth from the manufacturer’s specification sheet for your card or memory.

Two things follow. First, a bigger GPU only helps until the model already fits; two cards that both hold the 4.9 GB file differ in bandwidth, not capacity. Second, if the model does not fit and layers spill to system RAM, the much lower bandwidth of system memory becomes the effective ceiling for the spilled portion. Fitting the model is worth more than raw GPU speed, and the 8-bit Q8_0 build on a 12 GB card will be slower than Q4_K_M on the same card simply because there are more bytes to move.

Measured on an Apple M3 Pro (18 GB): 2 November 2026

llama3.1:8b generated 27.2 tokens per second on the one machine we own, an Apple M3 Pro (18 GB). The rest of the table is the same run, so you can see where it sits against the other small models.

Model (Ollama tag)ParamsQuantFileMeasured tok/sRun spreadCeilingShareDate
llama3.2:3b3.2BQ4_K_M2.02 GB55.653.4–55.87475%2026-11-02
qwen2.5-coder:3b-base3.1BQ4_K_M1.93 GB55.053.8–56.67871%2026-11-02
qwen3:4b4.0BQ4_K_M2.50 GB44.744.1–44.86075%2026-11-02
phi4-mini3.8BQ4_K_M2.49 GB43.742.8–45.26073%2026-11-02
mistral:7b7.2BQ4_K_M4.37 GB29.029.0–29.03484%2026-11-02
qwen2.5-coder:7b7.6BQ4_K_M4.68 GB29.028.9–29.03290%2026-11-02
llama3.1:8b8.0BQ4_K_M4.92 GB27.226.9–27.43089%2026-11-02
deepseek-r1:8b8.2BQ4_K_M5.23 GB25.425.4–25.52989%2026-11-02
qwen3:8b8.2BQ4_K_M5.23 GB25.325.2–25.32988%2026-11-02
gemma3:12b11.8BQ4_K_M7.31 GB16.716.1–16.82181%2026-11-02
deepseek-r1:14b14.8BQ4_K_M8.99 GB14.714.6–14.81788%2026-11-02
qwen2.5-coder:14b14.8BQ4_K_M8.99 GB14.514.4–14.61787%2026-11-02
qwen3:14b14.8BQ4_K_M9.28 GB14.514.4–14.51690%2026-11-02

Also measured: llama3.1:8b 49.2 tok/s on the NVIDIA L4 (24 GB) (rented cloud VM, Ollama 0.40.13, 2026-11-03).

Apple M3 Pro, 18 GB unified memory, Ollama 0.40.13, macOS 27.0.1 (Darwin 27.0.0, arm64), Metal. Median generation rate of 6 runs after a discarded warm-up, computed from Ollama's raw eval_count and eval_duration over its HTTP API (not scraped from the terminal); any run that produced fewer than 30 tokens is thrown out rather than averaged. The same prompt, 7 runs, for every model. Ceiling = 150 GB/s (Apple's figure for the M3 Pro) ÷ the file size Ollama downloaded. One machine is a data point, not a survey; download the script (MIT) if you want the same table for yours. Thinking models (qwen3, deepseek-r1) are timed over every token they emit, reasoning included. Every row is in the open benchmark dataset, with how each row is measured.

Read the measured row against the ceiling: 27.2 tok/s on a 150 GB/s machine with a 4.92 GB file is 89% of the bound, which is as close as a dense model gets. On the rented NVIDIA L4 (24 GB, 300 GB/s) the same tag measured 49.2 tok/s, 81% of its 61 tok/s bound (Ollama 0.40.13, 3 November 2026). Scale that share, not the raw number, to your own hardware’s bandwidth.

Benchmarks published by Meta: how good is Llama 3.1 8B?

Llama 3.1 8B Instruct scores 69.4 on MMLU (5-shot) on Meta’s model card, 73.0 with 0-shot chain-of-thought; the base model scores 66.7. These are Meta’s own results from its internal evaluation library. The card compares Llama 3.1 with Llama 3 and with the larger 3.1 models; it contains no figures for any other company’s models. The biggest moves over Llama 3 8B are in maths (MATH 29.1 → 51.9), code (HumanEval 60.4 → 72.6) and tool use (API-Bank 48.3 → 82.6); GPQA is the one row that went down.

Instruction-tuned models, copied from the Llama 3.1 model card with the shot setting Meta used.
BenchmarkLlama 3.1 8B InstructLlama 3 8B Instruct
MMLU (5-shot)69.468.5
MMLU (0-shot, CoT)73.065.3
MMLU-Pro (5-shot, CoT)48.345.5
IFEval80.476.8
ARC-C (0-shot)83.482.4
GPQA (0-shot)30.434.6
HumanEval (0-shot, pass@1)72.660.4
MBPP++ base (0-shot, pass@1)72.870.6
GSM-8K (8-shot, CoT)84.580.6
MATH (0-shot, CoT)51.929.1
API-Bank (tool use)82.648.3
BFCL (tool use)76.160.3
Nexus (tool use)38.518.1
Multilingual MGSM (0-shot, CoT)68.9—
Base (pretrained) models, same source.
BenchmarkLlama 3.1 8BLlama 3 8B
MMLU (5-shot)66.766.7
MMLU-Pro (5-shot, CoT)37.136.2
AGIEval English (3-5 shot)47.847.1
CommonSenseQA (7-shot)75.072.6
BIG-Bench Hard (3-shot, CoT)64.261.1
ARC-Challenge (25-shot)79.779.4
TriviaQA-Wiki (5-shot)77.678.5
SQuAD (1-shot)77.076.4
DROP (3-shot, F1)59.558.4
Multilingual MMLU (5-shot), 8B Instruct, from the same card. English is the 69.4 above.
LanguageMMLU
Portuguese62.12
Spanish62.45
French62.34
Italian61.63
German60.59
Hindi50.88
Thai50.32

Source: Meta’s Llama 3.1 model card. Other models’ scores on the same benchmarks are on the AI model leaderboard.

Specifications

Model family
llama-3-1
Version
3.1
Parameters
8,030,261,248 (Hugging Face API; the same count as Llama 3 8B)
Context window
128K tokens (131,072)
Modalities
text in, text and code out
Supported languages
English, German, French, Italian, Portuguese, Hindi, Spanish, Thai
Release date
23 July 2024
Knowledge cutoff
December 2023
Training data
~15 trillion tokens of publicly available data; fine-tuning data includes over 25M synthetically generated examples
Variants
Base (pretrained) and Instruct
License
Llama 3.1 Community License
Data verified
2026-10-15

Headline scores (instruct model)

Every figure is copied from Meta’s model card with the shot setting Meta used. Nothing here is this site’s own evaluation; the full tables are in the benchmarks section above.

  • MMLU: 69.4 % — Meta model card, instruct, 5-shot macro average (73.0 with 0-shot CoT)
  • MMLU-Pro (CoT): 48.3 % — Meta model card, instruct, 5-shot
  • IFEval: 80.4 % — Meta model card, instruct
  • GSM-8K: 84.5 % — Meta model card, instruct, 8-shot chain-of-thought
  • MATH: 51.9 % — Meta model card, instruct, 0-shot CoT final exact match
  • HumanEval: 72.6 % — Meta model card, instruct, 0-shot pass@1
  • ARC-Challenge: 83.4 % — Meta model card, instruct, 0-shot accuracy
  • GPQA: 30.4 % — Meta model card, instruct, 0-shot exact match

Architecture: what is inside Llama 3.1 8B

Llama 3.1 8B is a dense decoder-only transformer with grouped-query attention. The figures below are from the model’s config.json; they are identical to Llama 3 8B except for the maximum position count and the added RoPE scaling, which is how the same weights layout reaches 128K.

Layers32
Hidden size (model width)4,096
Feed-forward intermediate size14,336
Attention heads32
Key-value heads (GQA)8
Head dimension128
Vocabulary128,256 tokens
Max positions131,072
RoPEtheta 500,000; “llama3” scaling, factor 8 over an original 8,192
Activation / normSiLU; RMSNorm, eps 1e-5

From config.json (ungated mirror of Meta’s repository). The full generation-by-generation table of Llama dimensions is on the Llama 3 8B page.

How is Llama 3.1 8B different from Llama 3 8B?

Comparing the two model cards, four things changed that matter for local use:

  • Context 8K → 128K. The headline change, with the memory bill described above.
  • Tool calling. The 3.1 card reports tool-use benchmarks for the instruct model; on API-Bank the 8B went from 48.3 to 82.6.
  • Eight supported languages rather than English alone, with the multilingual MMLU scores above.
  • Knowledge cutoff December 2023 instead of March 2023, with roughly the same 15T-token pretraining budget.

Same parameter count, same architecture, and the same memory footprint at a given quantisation, so upgrading from Llama 3 8B costs you nothing but the download. The one caveat: the default Ollama tags differ (4.7 GB q4_0 for Llama 3, 4.9 GB Q4_K_M for 3.1), which is a format change, not a size change.

How do I install Llama 3.1 8B?

The one-line path is Ollama, which pulls the 4.9 GB Q4_K_M build and starts a chat session. Every tag below is on ollama.com/library/llama3.1/tags.

# Default: Q4_K_M, 4.9 GB — for an 8 GB card
ollama run llama3.1:8b

# Smaller: Q3_K_M, 4.0 GB — for a 6 GB card or an 8 GB machine with no GPU
ollama pull llama3.1:8b-instruct-q3_K_M

# Larger: Q8_0, 8.5 GB — for a 12 GB card
ollama pull llama3.1:8b-instruct-q8_0

# Raise the context window inside a session (default is 4,096 tokens)
/set parameter num_ctx 32768

Re-check the KV cache table before raising num_ctx. LM Studio and llama.cpp read the same GGUF files if you prefer a GUI or a raw binary; for a quantisation Ollama does not carry, download the file from the bartowski repository linked in the hardware section and load it in llama.cpp. The alternative is to take the weights straight from the vendor:

  1. Download the latest weights from Download Llama 3.1 8B. The Hugging Face repository is gated, so you accept Meta’s licence before downloading.
  2. Verify your hardware can accommodate the 8B parameter checkpoint at the context length you intend to use (the tables above).
  3. Follow the vendor documentation Hugging Face model card for runtime setup and inference examples. Tool calling from a local script is covered in the Ollama function-calling guide.

What is Llama 3.1 8B good and bad at?

Where an 8B model earns its place

  • • Summarising and rewriting documents you already have: the task is bounded, and the model is not being asked to know anything.
  • • Structured extraction: pulling JSON out of messy text, with the schema in the prompt.
  • • Drafting and boilerplate code, checked by you before it runs. Meta’s HumanEval figure is 72.6.
  • • Tool-calling agents where the model routes to a real API instead of answering from memory; the card’s tool-use rows are the largest gains over Llama 3.
  • • Anything privacy-bound, where the constraint is “this text must not leave the machine” rather than raw capability.

Where it will disappoint you

  • • Factual recall on niche topics. An 8B model has limited room for world knowledge, and the cutoff is December 2023; pair it with retrieval rather than trusting it.
  • • Hard reasoning. Meta’s own GPQA figure (30.4, lower than Llama 3 8B’s 34.6) is the honest signal: it is a competent assistant, not a solver.
  • • Very long contexts in practice. Whether attention quality holds at 128K is a different question from whether the window is advertised, and the memory bill above usually settles it first.
  • • Tasks where a 70B model is the right answer. If quality matters more than latency and you have the VRAM, compare against Llama 3.1 70B or Llama 3.3 70B.

Licence

Llama 3.1 is released under the Llama 3.1 Community License (version release date July 23, 2024). Meta describes it as a custom commercial licence; it is not an open-source licence such as MIT or Apache 2.0. The terms that matter in practice:

  • Commercial use is permitted, along with modification and redistribution.
  • If you distribute the model, a derivative, or a product or service that contains it, you must include the licence and “prominently display ‘Built with Llama’” on a related website, interface, blog post, about page or documentation.
  • A model you train or fine-tune from it and distribute must “include ‘Llama’ at the beginning of any such AI model name”.
  • If, on the release date, your products or services had more than 700 million monthly active users in the preceding month, you must request a separate licence from Meta.
  • Use is also subject to Meta’s Acceptable Use Policy, and the card lists use outside the eight supported languages as out of scope unless you fine-tune for it.

This is a summary, not legal advice; read the licence before building a product on it. Other model licences are compared in LLM licences for commercial use.

What has replaced Llama 3.1 8B

Nothing at the same size from Meta. Llama 3.1 8B is still the most recent 8B model in the Llama line, which is why it remains the default “small Llama” on Ollama:

  • Llama 3.2 added 1B and 3B text models and 11B and 90B vision models (its two model cards list those four sizes), with no 8B. See Llama 3.2 1B and 3B and Llama 3.2 11B Vision.
  • Llama 3.3 is a 70B-only release (its model card lists one size); there is no Llama 3.3 8B. See Llama 3.3 70B.
  • Llama 4 Scout (April 2025) is Meta’s next generation: a 109B mixture-of-experts model with 17B active parameters that accepts images. Its Ollama tag is 67 GB, so it is not a replacement for anything that runs on an 8 GB card.

If you want the strongest model that fits 8 or 12 GB rather than this model specifically, the best Ollama models list is kept current.

Frequently asked questions

What are the Llama 3.1 8B system requirements?

An 8 GB GPU, or 16 GB of system RAM without one, for the default 4.9 GB build at an 8K context; a 12 GB card for Q8_0 or a 32K context; a 24 GB card for the full 128K window or the fp16 build. Disk space equals the download size of the tag you pull. Any OS that runs Ollama, LM Studio or llama.cpp.

How much VRAM does Llama 3.1 8B use at Q4_K_M?

About 7 GB with an 8K context: the 4.92 GB file, 1.07 GB of context cache and roughly 1 GB of buffers. At the Ollama default of 4,096 tokens it is about 6.5 GB. That is calculated from the file size and the model configuration, not measured.

How big is Llama 3.1 8B in GB?

4.9 GB for the default Ollama tag. Other builds range from 3.2 GB (Q2_K) to 16 GB (fp16); the original BF16 safetensors on Hugging Face are about 16 GB as well.

What is the official MMLU score?

69.4 for the instruct model (5-shot) and 66.7 for the base model, from Meta’s model card. With 0-shot chain-of-thought the instruct model scores 73.0.

Is the 128K context length official?

Yes. Meta’s model card lists a 128k context length for the 8B, 70B and 405B, the configuration file sets 131,072 maximum positions, and the Ollama tags are listed with a 128K context window. Ollama still opens a 4,096-token window unless you set num_ctx.

Should I run Llama 3.1 8B or Llama 3 8B?

Llama 3.1 8B. Same hardware, same download time within 0.2 GB, higher scores on every card row except GPQA, and a 128K window instead of 8K.

Is Llama 3.1 8B good for coding?

Meta reports HumanEval 72.6 and MBPP++ 72.8 for the instruct model. For a dedicated local coding model at this size see the best coding LLM for 8 GB of VRAM.

Research & Documentation

Meta

Weights and sizes

Sourcing note: every specification and benchmark figure on this page comes from Meta’s model card and licence, linked above. The memory tables are arithmetic derived from the published parameter count, the model configuration and the published file sizes; the formulas are shown so you can check them. This site does not publish its own hardware benchmarks for this model.

Related Models & Resources

Other Llama models

Setup & Optimization Guides

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Barsha Mohapatra

Founder and Editor, Local AI Master · Founder, Little AI Master

Founder of Little AI Master and the editor behind every course and guide on Local AI Master. Years of tutoring students taught her where AI education actually fails.

📅 Published: 2024-07-23🔄 Last Updated: 2026-10-15✓ Manually Reviewed

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Last verified on October 15, 2026 by Localaimaster Team

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