GPT-5.5 wins more areas, narrowly.DeepSeek-V4-Flash-Vision-Exp is cheaper.
Scores updated · 13 tests both models report · How we compare
Where each one wins
Tests won in each of the four 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.
Reasoning, math 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-V4-Flash-Vision-Exp costs 98% 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
- Programming problems, refreshed regularlyLiveBench · Coding+14points ahead
- Fresh competition math problemsLiveBench · Mathematics+8.1points ahead
- Fresh logic puzzles that change regularlyLiveBench · Reasoning+4.3points ahead
Where DeepSeek-V4-Flash-Vision-Exp pulls ahead
- Fixes real GitHub issues, working as an agentLiveBench · Agentic Coding+11.1points ahead
Every test, side by side
All 13 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingEven
- LiveBench · CodingGPT-5.5 by 1468.282.2+14
- LiveBench · Agentic CodingDeepSeek-V4-Flash-Vision-Exp by 11.165.154+11.1
- Terminal-Bench 2.1tie83.984.3tie
Following instructionsEven
- LiveBench · Instruction Followingtie7170.7tie
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.
- DeepSWEGPT-5.5 by 10.759.370+10.7
- livebench_languageGPT-5.5 by 780.487.4+7
- NL2RepoDeepSeek-V4-Flash-Vision-Exp by 757.750.7+7
- CyberGymGPT-5.5 by 6.575.381.8+6.5
- Toolathlon VerifiedDeepSeek-V4-Flash-Vision-Exp by 2.475.973.5+2.4
- livebench_data_analysisGPT-5.5 by 2.179.581.6+2.1
- Agents' Last Examtie27.326.6tie
Questions people ask
Which is better, DeepSeek-V4-Flash-Vision-Exp or GPT-5.5?
GPT-5.5 wins two of the four areas where both have results: reasoning and math. DeepSeek-V4-Flash-Vision-Exp wins none, but costs 98% less. They are level on coding and following instructions.
Which is better for coding?
Neither. They win 1 coding test each of the 3 both models report, and 1 is a tie.
Which is cheaper?
DeepSeek-V4-Flash-Vision-Exp costs $0.22 per million input tokens and $0.65 per million output tokens; GPT-5.5 costs $5.00 and $30.00. That makes DeepSeek-V4-Flash-Vision-Exp about 98% cheaper for the same work.
How do you compare the two?
We use the 13 benchmark tests both models have published scores on. The verdict counts the 6 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.