Agentic
Not comparable- Claude Sonnet 5
- 65.8
- Supported · #11/152
- DeepSeek V4.1 Flash
- Not ranked
- Basis
- BenchAlign lane · 6 vs 8 public rows
- Reading
- Not comparable
Claude Sonnet 5 vs DeepSeek V4.1 Flash
Updated September 10, 2026. Public scores include evidence status and uncertainty. They are not guarantees for a specific workload.
Decision reading
At least one model is not scored in the current public ranking lane, so the page does not name an overall quality winner.
2 results are shared. Category rows resting on Estimated evidence or different benchmark sets are marked directional and do not name a winner.
Share or export
Which one for your work
Recommendations appear only when a shared evidence basis or an explicit operating constraint supports the call. Secondary and unsupported use cases stay disclosed below the initial list.
Chat turn cost
1K fresh input + 500 output tokens
DeepSeek V4.1 Flash
DeepSeek V4.1 Flash has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-rates
Cache-heavy agent loop cost
200K cached + 20K fresh input + 10K output tokens
DeepSeek V4.1 Flash
DeepSeek V4.1 Flash has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-rates
Show secondary and unsupported calls
Repository review cost
50K fresh input + 3K output tokens
DeepSeek V4.1 Flash
DeepSeek V4.1 Flash has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-rates
Coding work
Code generation, repair, and software-engineering tasks
Not enough matched evidence
DeepSeek V4.1 Flash is not ranked on the public lane for coding, so no winner is named for coding.
Confidence: limited
Agentic work
Tool use, computer use, and multi-step task completion
Not enough matched evidence
DeepSeek V4.1 Flash is not ranked on the public lane for agentic, so no winner is named for agentic.
Confidence: limited
Long documents
Prompts that approach the documented context limit
No clear pick
The documented context windows are equal.
Confidence: documented
What is actually comparable
Shared results can support a head-to-head reading. Results present for only one model describe coverage, not superiority.
22 Claude Sonnet 5 only
2 Shared
19 DeepSeek V4.1 Flash only
- Shared results
- 2
- Claude Sonnet 5 only
- 22
- DeepSeek V4.1 Flash only
- 19
- Like-for-like categories
- 0 / 8
Category results, on a stated basis
Each row shows the public-lane category score for both models: the BenchAlign lane for agentic, coding, and knowledge, and the weighted public rows elsewhere, with the same rank each model page reports. A row is like-for-like only when both scores rest on Supported evidence or the same weighted set. Directional and not-comparable rows remain visible, but they never receive a winner.
Coding
Not comparable- Claude Sonnet 5
- 64.1
- Supported · #13/151
- DeepSeek V4.1 Flash
- Not ranked
- Basis
- BenchAlign lane · 10 vs 6 public rows
- Reading
- Not comparable
Reasoning
Not comparable- Claude Sonnet 5
- 77.4
- Unranked · 2 rankable rows
- DeepSeek V4.1 Flash
- Not ranked
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Knowledge
Not comparable- Claude Sonnet 5
- 66.7
- Supported · #20/182
- DeepSeek V4.1 Flash
- Not ranked
- Basis
- BenchAlign lane · 6 vs 3 public rows
- Reading
- Not comparable
Math
Not comparable- Claude Sonnet 5
- Not ranked
- DeepSeek V4.1 Flash
- Not ranked
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Multilingual
Not comparable- Claude Sonnet 5
- Not ranked
- DeepSeek V4.1 Flash
- Not ranked
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Multimodal
Not comparable- Claude Sonnet 5
- 77.5
- #13/48
- DeepSeek V4.1 Flash
- Not ranked
- Basis
- Provisional lane · 1 vs 0 weighted rows
- Reading
- Not comparable
Instruction following
Not comparable- Claude Sonnet 5
- Not ranked
- DeepSeek V4.1 Flash
- Not ranked
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
| Category | Claude Sonnet 5 | DeepSeek V4.1 Flash | Basis | Reading |
|---|---|---|---|---|
| Agentic | 65.8Supported · #11/152 | Not ranked | Not comparableBenchAlign lane · 6 vs 8 public rows | Not comparable |
| Coding | 64.1Supported · #13/151 | Not ranked | Not comparableBenchAlign lane · 10 vs 6 public rows | Not comparable |
| Reasoning | 77.4Unranked · 2 rankable rows | Not ranked | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Knowledge | 66.7Supported · #20/182 | Not ranked | Not comparableBenchAlign lane · 6 vs 3 public rows | Not comparable |
| Math | Not ranked | Not ranked | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Multilingual | Not ranked | Not ranked | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Multimodal | 77.5#13/48 | Not ranked | Not comparableProvisional lane · 1 vs 0 weighted rows | Not comparable |
| Instruction following | Not ranked | Not ranked | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
Ranks count the models scored in each category’s lane, so the agentic, coding, and knowledge denominators (BenchAlign) differ from the provisional-lane categories. Unranked scores sit on the lane’s scale but never name a winner. Like-for-like rows within 0.5 points read as a practical tie.
Shape of the matched evidence
Only shared public evidence is shown. Sparse evidence stays a ruled list rather than being closed into a radar shape.
Too few matched category axes support a radar. The ruled list below shows only shared benchmark results; positions use each benchmark’s normalized display scale when available.
HLE
Knowledge
Claude Sonnet 5: 57.4%DeepSeek V4.1 Flash: 36.8%Normalized gap 20.6Claude Sonnet 5 source DeepSeek V4.1 Flash source
What each workload costs
Three fixed token mixes turn per-token rates into comparable decisions. Each scenario states context fit and whether cached input had to fall back to the published list-input rate.
Chat turn
1K fresh input + 500 output tokens
- Claude Sonnet 5
- $0.007
- Fits in one request
- DeepSeek V4.1 Flash
- $0.0009
- Fits in one request
DeepSeek V4.1 Flash has the lower modeled cost
Costs use the listed standard API rates.
Repository review
50K fresh input + 3K output tokens
- Claude Sonnet 5
- $0.13
- Fits in one request
- DeepSeek V4.1 Flash
- $0.0186
- Fits in one request
DeepSeek V4.1 Flash has the lower modeled cost
Costs use the listed standard API rates.
Cache-heavy agent loop
200K cached + 20K fresh input + 10K output tokens
- Claude Sonnet 5
- $0.18
- Fits in one request
- DeepSeek V4.1 Flash
- $0.0192
- Fits in one request
DeepSeek V4.1 Flash has the lower modeled cost
Costs use the listed standard API rates.
Specification differences
Sourced differences are shown directly. Missing facts stay explicit instead of being inferred from a model name or family.
SpecificationClaude Sonnet 5DeepSeek V4.1 Flash
Context window
Maximum documented context; output-token limits may be lower.
Claude Sonnet 5
DeepSeek V4.1 Flash
API model ID
Claude Sonnet 5
claude-sonnet-5
Anthropic model overviewDeepSeek V4.1 Flash
deepseek-flash
DeepSeek models and pricingCached-input rate
A missing cached-input rate falls back to the listed input rate only in the stated workload estimate.
Claude Sonnet 5
$0.2 per 1M cached input tokens
Claude API pricingDeepSeek V4.1 Flash
$0.006 per 1M cached input tokens
DeepSeek: Models & PricingDocumented inputs
Claude Sonnet 5
text, image
Anthropic model overviewDeepSeek V4.1 Flash
text, image
DeepSeek vision guideDocumented outputs
Claude Sonnet 5
DeepSeek V4.1 Flash
Provider availability
Claude Sonnet 5
Generally Available · Claude API
Anthropic model overviewDeepSeek V4.1 Flash
Generally Available · DeepSeek API, open weights
DeepSeek-V4.1-Flash releaseReasoning profile
Claude Sonnet 5
Reasoning
DeepSeek V4.1 Flash
Reasoning
Weight access
Claude Sonnet 5
Proprietary
DeepSeek V4.1 Flash
Open Weight
License
Claude Sonnet 5
Proprietary
DeepSeek V4.1 Flash
Open Weight
Release date
Claude Sonnet 5
2026-06-30
DeepSeek V4.1 Flash
2026-09-10
If you already use one of these models
- Deployment change
- The models list different providers, so authentication, endpoint behavior, limits, and feature support may change.
- Quality signal
- At least one model is not scored in the current public ranking lane, so the page does not name an overall quality winner.
- Workload cost
- Repository review: $0.13 vs $0.0186. Cache-heavy agent loop: $0.18 vs $0.0192.
- Context tradeoff
- Both models list 1M.
Run the same representative tasks against both endpoints before changing production traffic.
Benchmark evidence
The full public result ledger is available for audit without forcing a wide desktop table onto a phone.
Browse raw public benchmark evidence43 rows
Agentic
Terminal-Bench 3.0
Claude Sonnet 514.6%SourceDeepSeek V4.1 Flash—Not directly comparable
Terminal-Bench 2.0
Claude Sonnet 580.4%SourceDeepSeek V4.1 Flash—Not directly comparable
BrowseComp
Claude Sonnet 584.7%SourceDeepSeek V4.1 Flash—Not directly comparable
HLE w/ tools
Claude Sonnet 557.4%SourceDeepSeek V4.1 Flash63.9%SourceDeepSeek V4.1 Flash leads this result
OSWorld-Verified
Claude Sonnet 581.2%SourceDeepSeek V4.1 Flash—Not directly comparable
Terminal-Bench 2.1 (Vals)
Claude Sonnet 574.5%SourceDeepSeek V4.1 Flash—Not directly comparable
Terminal-Bench 2.1
Claude Sonnet 5—DeepSeek V4.1 Flash90.6%SourceNot directly comparable
terminalBench3
Claude Sonnet 5—DeepSeek V4.1 Flash30%SourceNot directly comparable
Terminal-Bench 4.0
Claude Sonnet 5—DeepSeek V4.1 Flash31.20%SourceNot directly comparable
CyberGym
Claude Sonnet 5—DeepSeek V4.1 Flash88.1%SourceNot directly comparable
ExploitGym
Claude Sonnet 5—DeepSeek V4.1 Flash15.3%SourceNot directly comparable
AutomationBench
Claude Sonnet 5—DeepSeek V4.1 Flash54.8%SourceNot directly comparable
Agents' Last Exam
Claude Sonnet 5—DeepSeek V4.1 Flash31.8%SourceNot directly comparable
Coding
SWE-bench Verified
Claude Sonnet 585.2%SourceDeepSeek V4.1 Flash—Not directly comparable
SWE-bench Pro
Claude Sonnet 563.2%SourceDeepSeek V4.1 Flash—Not directly comparable
SWE Multilingual
Claude Sonnet 578.3%SourceDeepSeek V4.1 Flash—Not directly comparable
SWE Multimodal
Claude Sonnet 528.1%SourceDeepSeek V4.1 Flash—Not directly comparable
Terminal-Bench 2.0
Claude Sonnet 580.4%SourceDeepSeek V4.1 Flash—Not directly comparable
FrontierCode 1.1 Main
Claude Sonnet 542.7%SourceDeepSeek V4.1 Flash—Not directly comparable
cursorBench32
Claude Sonnet 561.5%SourceDeepSeek V4.1 Flash—Not directly comparable
VulcanBench CII v1
Claude Sonnet 589.2%SourceDeepSeek V4.1 Flash—Not directly comparable
LiveCodeBench (Vals)
Claude Sonnet 582.4%SourceDeepSeek V4.1 Flash—Not directly comparable
SWE-bench (Vals)
Claude Sonnet 579.6%SourceDeepSeek V4.1 Flash—Not directly comparable
Codeforces
Claude Sonnet 5—DeepSeek V4.1 Flash3471.0SourceNot directly comparable
Terminal-Bench 2.1
Claude Sonnet 5—DeepSeek V4.1 Flash90.6%SourceNot directly comparable
terminalBench3
Claude Sonnet 5—DeepSeek V4.1 Flash30%SourceNot directly comparable
DeepSWE
Claude Sonnet 5—DeepSeek V4.1 Flash74.2%SourceNot directly comparable
ProgramBench
Claude Sonnet 5—DeepSeek V4.1 Flash20.3%SourceNot directly comparable
NL2Repo
Claude Sonnet 5—DeepSeek V4.1 Flash65.4%SourceNot directly comparable
Knowledge
HLE
Claude Sonnet 557.4%SourceDeepSeek V4.1 Flash36.8%SourceClaude Sonnet 5 leads this result
HLE w/o tools
Claude Sonnet 543.2%SourceDeepSeek V4.1 Flash—Not directly comparable
HLE-Verified
Claude Sonnet 531.0%SourceDeepSeek V4.1 Flash—Not directly comparable
LABBench2
Claude Sonnet 580.1%SourceDeepSeek V4.1 Flash—Not directly comparable
GPQA Diamond (Vals)
Claude Sonnet 588.9%SourceDeepSeek V4.1 Flash—Not directly comparable
MMLU-Pro (Vals)
Claude Sonnet 587.5%SourceDeepSeek V4.1 Flash—Not directly comparable
GPQA
Claude Sonnet 5—DeepSeek V4.1 Flash90.9%SourceNot directly comparable
GPQA-D
Claude Sonnet 5—DeepSeek V4.1 Flash90.9%SourceNot directly comparable
Math
Apex
Claude Sonnet 5—DeepSeek V4.1 Flash65.6%SourceNot directly comparable
Multimodal
CharXiv
Claude Sonnet 588.3%SourceDeepSeek V4.1 Flash—Not directly comparable
CharXiv w/o tools
Claude Sonnet 577%SourceDeepSeek V4.1 Flash—Not directly comparable
Chartography (tools)
Claude Sonnet 5—DeepSeek V4.1 Flash78.9%SourceNot directly comparable
BabyVision w/ Python
Claude Sonnet 5—DeepSeek V4.1 Flash89.6%SourceNot directly comparable
ZeroBench w/ Python
Claude Sonnet 5—DeepSeek V4.1 Flash49.0%SourceNot directly comparable
Frequently asked questions
Which is better, Claude Sonnet 5 or DeepSeek V4.1 Flash?
At least one model is not scored in the current public ranking lane, so the page does not name an overall quality winner. The page therefore keeps the decision tied to the specific documented workload.
Which is better for coding, Claude Sonnet 5 or DeepSeek V4.1 Flash?
DeepSeek V4.1 Flash is not ranked on the public lane for coding, so no winner is named for coding.
Which is better for agentic tasks, Claude Sonnet 5 or DeepSeek V4.1 Flash?
DeepSeek V4.1 Flash is not ranked on the public lane for agentic tasks, so no winner is named for agentic tasks.
Which costs less, Claude Sonnet 5 or DeepSeek V4.1 Flash?
For the stated presets, chat costs $0.007 on Claude Sonnet 5 and $0.0009 on DeepSeek V4.1 Flash; repository review costs $0.13 and $0.0186; the cache-heavy agent loop costs $0.18 and $0.0192. Costs use the listed standard API rates.
Which has the larger context window, Claude Sonnet 5 or DeepSeek V4.1 Flash?
Both models list the same context window, 1M.
Related comparisons
Last updated September 10, 2026
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