Model comparison

GPT-5.6 Sol vs Grok 4.6

GPT-5.6 Sol costs $4.00 / $20.00 and Grok 4.6 $2.00 / $6.00 per 1M input / output tokens. Both accept about 1M tokens of context, text, images and files.

GPT-5.6 Sol: sources list different prices. We use $4.00 / $20.00; OpenRouter shows $2.00 / $10.00. See every source.

OpenAI

GPT-5.6 Sol

Released Jul 9, 2026 · gpt-5.6-sol

xAI

Grok 4.6

Released Aug 12, 2026 · grok-4.6

Which one to choose

Picked by a published rule, not by an editor. Scenarios without data are left out.

Everyday requests

Grok 4.6

$0.014 vs $0.005 for 1,000 input and 500 output tokens.

Long prompts

Grok 4.6

A 500K-token prompt with a 2K-token answer costs $4.06 on GPT-5.6 Sol and $2.02 on Grok 4.6.

Context window

GPT-5.6 Sol

GPT-5.6 Sol: 1.05M tokens; Grok 4.6: 500K. Differences under 10% count as a tie.

How the verdicts are calculated
  • Everyday requests: lower cost for 1,000 input + 500 output tokens at standard rates.
  • Long prompts: lower cost for a 500K-token prompt and 2K-token answer, including long-context surcharges.
  • Context window: bigger window wins; differences under 10% count as a tie.
  • Mixed inputs: more input types accepted; a tie is not shown until multimodal benchmark scores are collected.

Not shown yet

  • Coding: needs SWE-bench Verified scores
  • Speed: needs independent output-speed measurements
  • Privacy: needs data-retention and training-use policies

Side by side

The better value in each row is marked. Observed from LiteLLM and OpenRouter, checked against vendor pricing pages.

SpecGPT-5.6 SolGrok 4.6
Input priceper 1M tokens$4.00$2.00 (better)
Output priceper 1M tokens$20.00$6.00 (better)
Cached inputper 1M tokens$0.40 (better)$0.50
Typical request1,000 input + 500 output tokens$0.014$0.005 (better)
Long-prompt pricingCompared on a 500K-token prompt$8.00 / $30.00 above 272K tokens$4.00 / $12.00 above 200K tokens (better)
Batch priceinput / output per 1M tokens$2.00 / $10.00
Context window1.05M tokens (better)500K tokens
Max output128K tokens450K tokens (better)
Knowledge cutoffFeb 2026Not disclosed
Input typesText, Images, Files (PDF)Text, Images, Files (PDF)
ReasoningAdjustable effort (better)Always on
Tool useYesYes
Structured output (JSON)YesYes
BenchmarksGPQA Diamond, SWE-bench Verified, AIME 2025, LMArenaNot collected yetNot collected yet
Output speedtokens per secondNot collected yetNot collected yet