DeepSeek-V3 vs GPT-5.5
Wins 1 of 6 areas
Facts
Wins 5 of 6 areas
Coding · Agents · Reasoning · Long documents · Following instructions
GPT-5.5 is the stronger all-rounder.DeepSeek-V3 is cheaper and better at facts.
Scores updated · 24 tests both models report · How we compare
Where each one wins
Tests won in each of the six areas where both have results. Each piece is one test, so a longer bar means more evidence; grey means the two scored within a point of each other.
- ReasoningHard problems that need careful thinking04GPT-5.54 of 4 tests
- CodingWriting and fixing software03GPT-5.53 of 3 tests
- AgentsCarrying out multi-step tasks on its own03GPT-5.53 of 3 tests
- Long documentsFinding answers in very long texts01GPT-5.51 of 1 test
- Following instructionsDoing exactly what it is asked01GPT-5.51 of 1 test
- FactsGetting facts right instead of making them up21DeepSeek-V32 of 3 tests
Long documents and following instructions 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.
DeepSeek-V3 costs 97% 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-5.5 pulls ahead
- Command-line tasks in a real terminalTerminal-Bench 2.1+67.4points ahead
- Common-sense trick questionsSimpleBench+50.1points ahead
- Hard command-line tasks in a real terminalTerminal-Bench Hard+45.4points ahead
Where DeepSeek-V3 pulls ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+3.1points ahead
Every test, side by side
All 24 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingGPT-5.5
- Terminal-Bench 2.1GPT-5.5 by 67.416.984.3+67.4
- Terminal-Bench HardGPT-5.5 by 45.415.260.6+45.4
- SciCodeGPT-5.5 by 16.83955.8+16.8
AgentsGPT-5.5
- GDPValGPT-5.5 by 42.7042.7+42.7
- τ-Bench V3 · BankingGPT-5.5 by 34.34.739+34.3
- Terminal-Bench 4.0GPT-5.5 by 14.6014.6+14.6
ReasoningGPT-5.5
- SimpleBenchGPT-5.5 by 50.118.969+50.1
- Humanity's Last ExamGPT-5.5 by 41.14.745.8+41.1
- GPQA DiamondGPT-5.5 by 2865.593.5+28
- CritPtGPT-5.5 by 27.1027.1+27.1
FactsDeepSeek-V3
- AA-Omniscience · AccuracyGPT-5.5 by 32.525.458+32.5
- Vectara HHEM hallucination ratelower is betterDeepSeek-V3 by 3.26.19.3+3.2
- AA-Omniscience · Non-hallucinationDeepSeek-V3 by 3.114.111+3.1
Other results9 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.
- AA-OmniscienceGPT-5.5 by 61.2-40.720.5+61.2
- Artificial Analysis Coding IndexGPT-5.5 by 51.92374.9+51.9
- τ²-Bench Telecom (AA run)GPT-5.5 by 46.847.193.9+46.8
- AA IntelligenceGPT-5.5 by 28.79.738.4+28.7
- SuperGPQAGPT-5.5 by 1953.772.7+19
- LiveBenchGPT-5.5 by 8.372.480.7+8.3
- vectara_avg_summary_lengthGPT-5.5 by 47.9 rating points81.7129.6+47.9 rating
- vectara_factual_consistencyDeepSeek-V3 by 3.293.990.7+3.2
- vectara_answer_rateGPT-5.5 by 2.597.5100+2.5
Questions people ask
Which is better, DeepSeek-V3 or GPT-5.5?
GPT-5.5 wins five of the six areas where both have results: coding, agents, reasoning, long documents and following instructions. DeepSeek-V3 wins facts, and costs 97% less.
Which is better for coding?
GPT-5.5. It wins 3 of the 3 coding tests both models report; DeepSeek-V3 wins none.
Which is cheaper?
DeepSeek-V3 costs $0.24 per million input tokens and $0.90 per million output tokens; GPT-5.5 costs $5.00 and $30.00. That makes DeepSeek-V3 about 97% cheaper for the same work.
How do you compare the two?
We use the 24 benchmark tests both models have published scores on. The verdict counts the 15 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 9 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.