GPT-5.6 Sol vs Grok 4.3
Wins 6 of 8 areas
Coding · Agents · Reasoning · Images and charts · Math · Long documents
Wins 0 of 8 areas
—
GPT-5.6 Sol is the stronger all-rounder.Grok 4.3 is cheaper.
Scores updated · 30 tests both models report · How we compare
Where each one wins
Tests won in each of the eight areas we test. Each piece is one test, so a longer bar means more evidence; grey means the two scored within a point of each other.
- CodingWriting and fixing software60GPT-5.6 Sol6 of 6 tests
- AgentsCarrying out multi-step tasks on its own50GPT-5.6 Sol5 of 5 tests
- ReasoningHard problems that need careful thinking40GPT-5.6 Sol4 of 4 tests
- Images and chartsUnderstanding pictures, charts and video20GPT-5.6 Sol2 of 2 tests
- MathCompetition and research-level math10GPT-5.6 Sol1 of 1 test
- Long documentsFinding answers in very long texts10GPT-5.6 Sol1 of 1 test
- FactsGetting facts right instead of making them up11Even1 each
- Following instructionsDoing exactly what it is asked11Even1 each
Math and long documents rest on a single test each.
What it costs
Prices per million tokens, roughly 750,000 words. The bars show the cost of a million tokens read plus a million written.
Grok 4.3 costs 84% less for the same work.
The biggest differences
The tests each model wins by the widest margin, up to three each. Scores are out of 100.
Where GPT-5.6 Sol pulls ahead
- Command-line tasks in a real terminalTerminal-Bench 2.1+48.3points ahead
- Fixes real GitHub issues, working as an agentLiveBench · Agentic Coding+37.7points ahead
- Real work tasks from 44 professionsGDPVal+33.6points ahead
Where Grok 4.3 pulls ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+66.4points ahead
- Follows unfamiliar, precisely checkable instructionsIFBench+8.6points ahead
Every test, side by side
All 30 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingGPT-5.6 Sol
- Terminal-Bench 2.1GPT-5.6 Sol by 48.38839.7+48.3
- LiveBench · Agentic CodingGPT-5.6 Sol by 37.756.218.5+37.7
- Terminal-Bench HardGPT-5.6 Sol by 2865.937.9+28
- LMArena · WebDevGPT-5.6 Sol by 263 rating points16201357+263 rating
- LiveBench · CodingGPT-5.6 Sol by 1483.969.9+14
- SciCodeGPT-5.6 Sol by 8.857.148.3+8.8
AgentsGPT-5.6 Sol
- Terminal-Bench 4.0GPT-5.6 Sol by 39.939.90+39.9
- GDPValGPT-5.6 Sol by 33.655.622+33.6
- τ-Bench V3 · BankingGPT-5.6 Sol by 31.944.312.4+31.9
- AA IT-Bench SREGPT-5.6 Sol by 23.556.232.7+23.5
- AA ApexAgentsGPT-5.6 Sol by 22.939.917+22.9
ReasoningGPT-5.6 Sol
- CritPtGPT-5.6 Sol by 24.332.38+24.3
- LiveBench · ReasoningGPT-5.6 Sol by 20.991.770.8+20.9
- Humanity's Last ExamGPT-5.6 Sol by 12.349.537.2+12.3
- GPQA DiamondGPT-5.6 Sol by 494.190.1+4
FactsEven
- AA-Omniscience · Non-hallucinationGrok 4.3 by 66.47.874.2+66.4
- AA-Omniscience · AccuracyGPT-5.6 Sol by 24.659.434.8+24.6
Images and chartsGPT-5.6 Sol
- MMMU-ProGPT-5.6 Sol by 5.383.478.1+5.3
- LMArena · VisionGPT-5.6 Sol by 50 rating points12791229+50 rating
Following instructionsEven
- LiveBench · Instruction FollowingGPT-5.6 Sol by 9.171.862.8+9.1
- IFBenchGrok 4.3 by 8.672.781.3+8.6
Other results7 tests, not counted
Tests outside the eight areas. They are not counted above: several are summary scores built from other tests, or the same test under another name.
- Artificial Analysis Coding IndexGPT-5.6 Sol by 35.277.442.2+35.2
- AA Agentic IndexGPT-5.6 Sol by 33.350.517.2+33.3
- livebench_data_analysisGPT-5.6 Sol by 2479.855.8+24
- AA IntelligenceGPT-5.6 Sol by 22.14724.9+22.1
- livebench_languageGPT-5.6 Sol by 14.187.773.6+14.1
- τ²-Bench Telecom (AA run)Grok 4.3 by 12.685.197.7+12.6
- AA-OmniscienceGPT-5.6 Sol by 42218+4
Questions people ask
Which is better, GPT-5.6 Sol or Grok 4.3?
GPT-5.6 Sol wins six of the eight areas we test: coding, agents, reasoning, images and charts, math and long documents. Grok 4.3 wins none, but costs 84% less. They are level on facts and following instructions.
Which is better for coding?
GPT-5.6 Sol. It wins 6 of the 6 coding tests both models report; Grok 4.3 wins none.
Which is cheaper?
GPT-5.6 Sol costs $4.00 per million input tokens and $20.00 per million output tokens; Grok 4.3 costs $1.25 and $2.50. That makes Grok 4.3 about 84% cheaper for the same work.
How do you compare the two?
We use the 30 benchmark tests both models have published scores on. The verdict counts the 23 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 7 are listed but not counted, because several are summary scores or repeat a test. Each score is the one shown on the model's own page.