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Grok-4 vs Mercury 3

Grok-4 and Mercury 3 are closely matched at 33.5 and 36.1 on the LLM Stats Score. Mercury 3 is 36.9x cheaper per token.

xAI · Inception · Updated for 2026

Which is better?

Grok-4 and Mercury 3 are closely matched on the overall LLM Stats Score at 33.5 and 36.1.

In the 1 individual benchmarks reported for both models, Mercury 3 wins 1; this is a narrower head-to-head signal than the composite indexes.

On price, Mercury 3 is roughly 36.9x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Mercury 3 also accepts a larger context window (1,000,000 input tokens), making it the stronger choice for long documents and large codebases.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose Grok-4

  • you want predictable pricing at $3.00/M input and $15.00/M output

Choose Mercury 3

  • you value its reported benchmark strengths — it wins 1 of 1 exact shared results
  • cost matters — it's about 36.9x cheaper per token
  • you process long inputs — it offers a 1,000,000 token context window
  • you want the most recent training data — it shipped Oct 2026

At a glance

The differences that matter most.

Core performance indexes
33.5
#119
36.1
#98
32.7
#120
34.8
#103
17.1
#142
21.5
#105
Cost, coverage & limits
Benchmark wins
0 of 1
1 of 1
Input price
$3.00 / M
$0.10 / M
Output price
$15.00 / M
$0.35 / M
Context window
256,000
1,000,000

Individual benchmarks

7 reported for Grok-4 · 12 for Mercury 3

1 shared

Grok-4 outperforms in 0 benchmarks, while Mercury 3 is better at 1 benchmark (GPQA).

Mercury 3 significantly outperforms across most benchmarks.

Thu Oct 22 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

Mercury 3 costs less

For input processing, Grok-4 ($3.00/1M tokens) is 30.0x more expensive than Mercury 3 ($0.10/1M tokens).

For output processing, Grok-4 ($15.00/1M tokens) is 42.9x more expensive than Mercury 3 ($0.35/1M tokens).

In conclusion, Grok-4 is more expensive than Mercury 3.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Thu Oct 22 2026 • llm-stats.com
xAI
Grok-4
Input tokens$3.00
Output tokens$15.00
Best providerxAI
Inception
Mercury 3
Input tokens$0.10
Output tokens$0.35
Best providerInception
Notice missing or incorrect data?

Context Window

Maximum input and output token capacity

Mercury 3 accepts 1,000,000 input tokens compared to Grok-4's 256,000 tokens. Mercury 3 can generate longer responses up to 131,072 tokens, while Grok-4 is limited to 8,000 tokens.

xAI
Grok-4
Input256,000 tokens
Output8,000 tokens
Inception
Mercury 3
Input1,000,000 tokens
Output131,072 tokens
Thu Oct 22 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Grok-4 supports multimodal inputs, whereas Mercury 3 does not.

Grok-4 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Grok-4

Text
Images
Audio
Video

Mercury 3

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Grok-4

Proprietary

Closed source

Mercury 3

Proprietary

Closed source

Release Timeline

When each model was launched

Grok-4 was released on 2025-07-09, while Mercury 3 was released on 2026-10-19.

Mercury 3 is 16 months newer than Grok-4.

Grok-4

Jul 9, 2025

1.3 years ago

Mercury 3

Oct 19, 2026

3 days ago

1.3yr newer

Knowledge Cutoff

When training data ends

Grok-4 has a documented knowledge cutoff of 2024-12-31, while Mercury 3's cutoff date is not specified.

We can confirm Grok-4's training data extends to 2024-12-31, but cannot make a direct comparison without Mercury 3's cutoff date.

Grok-4

Dec 2024

Mercury 3

—

Provider Availability

Grok-4 is available from xAI. Mercury 3 is available from Inception.

Grok-4

xai logo
xAI
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M

Mercury 3

inception logo
Inception
Input Price:Input: $0.10/1MOutput Price:Output: $0.35/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Grok-4 and Mercury 3 side-by-side, then vote on the output you prefer.

Grok-4
✓ Preferred
Mercury 3
Open in Playground

FAQ

Common questions about Grok-4 vs Mercury 3.

Which is better, Grok-4 or Mercury 3?

Grok-4 and Mercury 3 are closely matched on the LLM Stats Score at 33.5 and 36.1. Grok-4 is made by xAI and Mercury 3 is made by Inception. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Grok-4 compare to Mercury 3 in benchmarks?

Grok-4 scores AIME 2025: 91.7%, HMMT25: 90.0%, GPQA: 87.5%, LiveCodeBench: 79.0%, Humanity's Last Exam: 40.0%. Mercury 3 scores GPQA: 89.2%, AA-LCR: 77.7%, IFBench: 76.8%, MRCR v2: 75.5%, DeepSearchQA: 71.3%.

Is Grok-4 cheaper than Mercury 3?

Mercury 3 is 30.0x cheaper for input tokens. Grok-4 costs $3.00/M input and $15.00/M output via xai. Mercury 3 costs $0.10/M input and $0.35/M output via inception.

What are the context window sizes for Grok-4 and Mercury 3?

Grok-4 supports 256K tokens and Mercury 3 supports 1.0M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Grok-4 and Mercury 3?

Key differences include LLM Stats Score (33.5 vs 36.1), context window (256K vs 1.0M), input pricing ($3.00 vs $0.10/M), multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes Grok-4 and Mercury 3?

Grok-4 is developed by xAI and Mercury 3 is developed by Inception.