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Llama 3.1 8B Instruct vs Grok 4.20

vs
Grok 4.20

xAI

89#46
Signal-by-Signal Comparison
SignalLlama 3.1 8B InstructDeltaGrok 4.20
Capabilities
50
-50
100
Benchmarks
44
-42
86
Pricing
100
+2
98
Context window size
81
-19
100
Recency
0
-100
100
Output Capacity
85
+65
20
Overall Result
2 wins
of 6
4 wins
Grok 4.20 wins 4 of 6 signals

Score History

Score History (25 data points)
Llama 3.1 8B InstructGrok 4.20
Llama 3.1 8B Instruct

44.5

current score

Leader

Grok 4.20

right now

Grok 4.20

88.8

current score

LMMarketCap.com
Interactive Price Comparison
100Kcalls/month
1,000tokens (~1,333 chars)
500tokens (~667 chars)

Llama 3.1 8B Instruct

Meta

Best Value
Per request$0.000090
Daily$0.30
Monthly$9.00
Annual$108.00

Grok 4.20

xAI

Per request$0.002500
Daily$8.33
Monthly$250.00
Annual$3000.00

Llama 3.1 8B Instruct saves you $241.00/month

That's $2892.00/year compared to Grok 4.20 at your current usage level of 100K calls/month.

96% cheaper
Choose Llama 3.1 8B Instruct for cost optimization

Llama 3.1 8B Instruct pricing:
Input:$0.05/M tokens
Output:$0.08/M tokens
Grok 4.20 pricing:
Input:$1.25/M tokens
Output:$2.50/M tokens
Llama 3.1 8B Instruct

Meta

45

Composite Score

Winner
Grok 4.20

xAI

89

Composite Score

Signal-by-Signal Comparison
MetricLlama 3.1 8B InstructGrok 4.20Winner
Overall Score
45
89
Grok 4.20
Rank#230#46
Grok 4.20
Quality Rank#230#46
Grok 4.20
Adoption Rank#230#46
Grok 4.20
Parameters8B----
Context Window131K2000K
Grok 4.20
Pricing$0.05/$0.08/M$1.25/$2.50/M--
Signal Scores
Capabilities
50
100
Grok 4.20
Benchmarks
44
86
Grok 4.20
Pricing
100
98
Llama 3.1 8B Instruct
Context window size
81
100
Grok 4.20
Recency
0
100
Grok 4.20
Output Capacity
85
20
Llama 3.1 8B Instruct
Benchmark Head-to-Head(12 benchmarks)
Llama 3.1: 0Grok 4.20: 5
Llama 3.1
Grok 4.20
Normalized 0-100%
MMLU
-91.5%
MMLU-Pro
30.37%83.5%
GPQA Diamond
-82%
MATH-500
-95%
HumanEval
69.5%95.5%
SWE-bench Verified
-70%
AIME 2024
-88%
IFEval
72.05%91%
BBH
30.85%90%
Arena Elo
12111462
LiveBench
-73%
BigCodeBench
32.8%-
Benchmark Interpretation

Our score (0-100) is driven by benchmark performance (90%) from Arena Elo ratings, MMLU, GPQA, HumanEval, SWE-bench, and 15+ standardized evaluations. Capabilities and context window serve as tiebreakers (10%). Learn more about our methodology.

Llama 3.1 8B InstructEntry Level

Scores 45/100 (rank #230), placing it in the top 21% of all 290 models tracked.

Raw Quality0/100
Cost Efficiency0/100
Speed0/100
Grok 4.20Elite Tier

Scores 89/100 (rank #46), placing it in the top 84% of all 290 models tracked.

Raw Quality0/100
Cost Efficiency0/100
Speed0/100

Grok 4.20 has a 44-point advantage, which typically translates to noticeably stronger performance on complex reasoning, code generation, and multi-step tasks.

When to Use Each Model

Choose Llama 3.1 8B Instruct when you need:

  • High-volume production workloads where API costs must be minimized
  • Self-hosted deployments where you need full control over the model

Choose Grok 4.20 when you need:

  • Processing long documents or large codebases (2000K token context)
  • Multimodal workflows that require image understanding
  • Step-by-step reasoning and chain-of-thought problem solving
Cost-Performance Analysis
Llama 3.1 8B InstructBest Value
Input cost$0.05/M tokens
Output cost$0.08/M tokens
Cost per quality point$0.003
Est. monthly (1M tokens/day)$1.95
Grok 4.20
Input cost$1.25/M tokens
Output cost$2.50/M tokens
Cost per quality point$0.042
Est. monthly (1M tokens/day)$56.25

Llama 3.1 8B Instruct offers 97% better value per quality point. At 1M tokens/day, you'd spend $1.95/month with Llama 3.1 8B Instruct vs $56.25/month with Grok 4.20 - a $54.30 monthly difference.

Latency & Speed
Llama 3.1 8B InstructFaster
Speed score0/100
Grok 4.20
Speed score0/100

Both models have comparable response speeds. For most applications, the latency difference is negligible.

When latency matters most: Interactive chatbots, IDE code completion, real-time translation, and user-facing applications where response time directly impacts experience. For batch processing, background summarization, or offline analysis, latency is less critical.

Example Use Cases

Code generation & review

Based on overall model capabilities and architecture for coding tasks like generating functions, debugging, and refactoring

Llama 3.1 8B Instruct

Customer support chatbot

Suitable for user-facing chat with competitive response times. Llama 3.1 8B Instruct also offers lower per-token costs for high-volume support

Llama 3.1 8B Instruct

Long document analysis

Larger context window (2000K tokens) can process longer documents, contracts, and research papers in a single pass

Grok 4.20

Batch data extraction

Lower output pricing ($0.08/M) reduces costs when processing thousands of records daily

Llama 3.1 8B Instruct

Creative writing & content

Higher overall composite score (89/100) correlates with better nuance, coherence, and style in long-form content

Grok 4.20

Image understanding & OCR

Supports vision input - can analyze screenshots, diagrams, photos, and scanned documents directly

Grok 4.20
Which Should You Choose?
Our recommendation:
Grok 4.20

Grok 4.20 clearly outperforms Llama 3.1 8B Instruct with a significant 44.3-point lead. For most general use cases, Grok 4.20 is the stronger choice. However, Llama 3.1 8B Instruct may still excel in niche scenarios.

by Meta

  • Choose for Quality - Marginally better benchmark scores; both are excellent
  • Choose for Cost - 97% lower pricing; better value at scale
  • Choose for Reliability - Higher uptime and faster response speeds
  • Choose for Prototyping - Stronger community support and better developer experience
  • Choose for Production - Wider enterprise adoption and proven at scale
Grok 4.20
Recommended

by xAI

Consider for specialized use cases.

Capability Comparison
CapabilityLlama 3.1 8B InstructGrok 4.20
Vision (Image Input)differs
Function Calling
Streaming
JSON Mode
Reasoningdiffers
Web Searchdiffers
Image Output
Monthly Cost Calculator
1,000tokens (600 in / 400 out)
100requests/day (3,000/month)

Llama 3.1 8B Instruct

Meta

Best Value
$0.1860
estimated monthly cost

Grok 4.20

xAI

$5.25
estimated monthly cost

Llama 3.1 8B Instruct saves you $5.06/month

That's 96% cheaper than Grok 4.20 at 1,000 tokens/request and 100 requests/day.

Assumes 60% input / 40% output token ratio per request. Actual costs may vary based on your usage pattern.

Parameters & Context
ParameterLlama 3.1 8B InstructGrok 4.20
Context Window131K2M
Max Output Tokens131,072--
Open SourceYesNo
CreatedJul 23, 2024Mar 31, 2026
Last updated: 28m ago

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