Head-to-head comparison across 3benchmark categories. Overall scores shown here use BenchLM's provisional ranking lane.
Claude Sonnet 5
94
DeepSeek V4 Flash (High)
70
Verified leaderboard positions: Claude Sonnet 5 unranked · DeepSeek V4 Flash (High) #28
Pick Claude Sonnet 5 if you want the stronger benchmark profile. DeepSeek V4 Flash (High) only becomes the better choice if coding is the priority or you want the cheaper token bill.
Agentic
+26.4 difference
Coding
+9.0 difference
Knowledge
+0.2 difference
Claude Sonnet 5
DeepSeek V4 Flash (High)
$3 / $15
$0.14 / $0.28
N/A
N/A
N/A
N/A
1M
1M
Pick Claude Sonnet 5 if you want the stronger benchmark profile. DeepSeek V4 Flash (High) only becomes the better choice if coding is the priority or you want the cheaper token bill.
Claude Sonnet 5 is clearly ahead on the provisional aggregate, 94 to 70. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
Claude Sonnet 5's sharpest advantage is in agentic, where it averages 81.8 against 55.4. The single biggest benchmark swing on the page is BrowseComp, 84.7% to 53.5%. DeepSeek V4 Flash (High) does hit back in coding, so the answer changes if that is the part of the workload you care about most.
Claude Sonnet 5 is also the more expensive model on tokens at $3.00 input / $15.00 output per 1M tokens, versus $0.14 input / $0.28 output per 1M tokens for DeepSeek V4 Flash (High). That is roughly 53.6x on output cost alone.
Claude Sonnet 5 is ahead on BenchLM's provisional leaderboard, 94 to 70. The biggest single separator in this matchup is BrowseComp, where the scores are 84.7% and 53.5%.
Claude Sonnet 5 has the edge for knowledge tasks in this comparison, averaging 57.4 versus 57.2. Inside this category, HLE is the benchmark that creates the most daylight between them.
DeepSeek V4 Flash (High) has the edge for coding in this comparison, averaging 72.2 versus 63.2. Inside this category, Terminal-Bench 2.0 is the benchmark that creates the most daylight between them.
Claude Sonnet 5 has the edge for agentic tasks in this comparison, averaging 81.8 versus 55.4. Inside this category, BrowseComp is the benchmark that creates the most daylight between them.
For engineers, researchers, and the plain curious — a weekly brief on new models, ranking shifts, and pricing changes.
Free. No spam. Unsubscribe anytime.