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Model Comparison

Claude Sonnet 5 vs DeepSeek V4 Pro 0423Which Is Better in 2026?

Claude Sonnet 5 vs DeepSeek V4 Pro 0423: which should you choose in 2026?

Claude Sonnet 5 (by Anthropic) and DeepSeek V4 Pro 0423 (by DeepSeek) are compared below. Here is how they stack up on benchmarks, price, and capabilities, and which one to pick in 2026.

No protocol-matched benchmark supports a controlled winner. Looking only at published point scores, Claude Sonnet 5 is higher on 1 benchmark (LiveBench), while DeepSeek V4 Pro 0423 is higher on 0 benchmarks.

The evaluation setups are not fully aligned, so these are not controlled head-to-head wins.

DeepSeek V4 Pro 0423 is about 4.1× cheaper on a blended 3:1 input/output basis ($0.97875 vs $4.00 per 1M tokens).

Choose Claude Sonnet 5 if…

  • • you need image inputs

Choose DeepSeek V4 Pro 0423 if…

  • • lower blended API cost matters for your workload

The benchmark count includes only results measured with a matching benchmark version and protocol. Arena scores are shown separately. Missing, preliminary, and incompatible data is not treated as a controlled win. Published point-score comparisons are labeled separately when protocol details are incomplete. For text-output models, the verdict also compares token pricing and context windows.

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Performance benchmarks

Every value links to its source. A dash means that no reviewed result is available for that exact model and protocol.

Claude Sonnet 5 and DeepSeek V4 Pro 0423 benchmark results
BenchmarkClaude Sonnet 5DeepSeek V4 Pro 0423
AutomationBench-AA

A 657-task benchmark of multi-step work across simulated SaaS applications in six business domains. The Artificial Analysis protocol reports a guardrail-aware score and is distinct from both the public Zapier split and the unrelated dynamic AutoBench framework.

Guardrail-aware score

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BrowseComp

A benchmark of difficult, verifiable information-seeking questions designed to measure an agent's ability to locate hard-to-find facts through web browsing.

Accuracy

——
OSWorld-Verified

A verified computer-use benchmark in which multimodal agents operate desktop applications and are graded from the resulting environment state.

Mean task reward

——
DeepSWE 1.1

A long-horizon software-engineering benchmark with 113 original tasks graded by hand-written tests.

Pass@1

54.0%±4.0
DataCurve
—
SWE-Bench Verified

A human-validated subset of real GitHub issues used to measure whether a coding agent can produce repository patches that resolve the associated tests.

Resolved

——
Terminal-Bench 2.1

Version 2.1 of the benchmark for completing realistic tasks in terminal environments. Harness, resource limits, and attempt count are part of the protocol.

Mean task success

74.6%±1.6
Terminal-Bench
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AutoBench

A dynamic LLM evaluation framework in which models generate questions, answer them, and participate in reciprocal peer assessment. AutoBench is distinct from Zapier's AutomationBench.

Weighted peer-assessment score

——
GPQA Diamond

The highest-quality subset of Graduate-Level Google-Proof Q&A, designed to test expert-level scientific reasoning in biology, physics, and chemistry.

Accuracy

—
Humanity's Last Exam

A 2,500-question expert-level benchmark spanning dozens of academic fields. Tool-assisted and no-tools results are separate protocols and must not be merged.

Accuracy

—
LiveBench

A contamination-resistant benchmark refreshed on a fixed release cadence. Scores from different LiveBench releases must never be compared as the same protocol.

Mean of category averages

Protocols differ or are incompletely disclosed; not counted as a controlled win

Arena preference scores
Arena (Text)

Human preference score

—
1457 ±4
Arena (Code/WebDev)

Human preference score for code and web development

—
1446 ±6

Pricing, capabilities, and model facts

Claude Sonnet 5 and DeepSeek V4 Pro 0423 model facts
FeatureClaude Sonnet 5DeepSeek V4 Pro 0423
Context & model facts
DeveloperAnthropicDeepSeek
API providerAnthropicDeepSeek
Input context1,000,000 tokens1,048,576 tokens
Maximum output128,000 tokens384,000 tokens
Released——
Added to WritingmateJun 30, 2026Apr 24, 2026
LicenseNot availableNot available
Knowledge cutoff——
Capabilities
InputsText, Image, FileText
OutputsTextText
Provider endpoint accepts tool parametersYesYes
ReasoningYesYes
VisionYesNo
Image GenerationNoNo
Video GenerationNoNo
API pricing
Input (per 1M tokens)$2.00$0.783
Output (per 1M tokens)$10.00$1.57
Blended 3:1 input/output$4.00$0.97875
API performance
p95 latencyNot measuredNot measured
Output throughputNot measuredNot measured
Writingmate shows API performance only when both models have enough observations from the same measurement window, prompt profile, and provider. Third-party latency values are not copied into this table.

Data sources

  • Writingmate model catalog (pricing, limits, and availability)

Catalog data last updated Jun 30, 2026.

Why Pay for Multiple Subscriptions?

Comparing Claude Sonnet 5 from Anthropic with DeepSeek V4 Pro 0423 from DeepSeek? Instead of managing separate API keys and subscriptions, get both with Writingmate.

Subscription-plan access for Claude Sonnet 5 and DeepSeek V4 Pro 0423
PlanPriceClaude Sonnet 5DeepSeek V4 Pro 0423AI ImagesAI Video
Writingmate Pro
Most popular
$20/moIncludedIncludedNano Banana Pro, FLUX.2, DALL-E & moreSora 2, VEO 3.1
Writingmate Ultimate
Power users
$60/moIncludedIncludedNano Banana Pro, FLUX.2, DALL-E & moreSora 2, VEO 3.1

Claude Sonnet 5 vs DeepSeek V4 Pro 0423 FAQ

Which is better, Claude Sonnet 5 or DeepSeek V4 Pro 0423?

No protocol-matched benchmark supports a controlled winner. Looking only at published point scores, Claude Sonnet 5 is higher on 1 benchmark (LiveBench), while DeepSeek V4 Pro 0423 is higher on 0 benchmarks. The evaluation setups are not fully aligned, so these are not controlled head-to-head wins. DeepSeek V4 Pro 0423 is about 4.1× cheaper on a blended 3:1 input/output basis ($0.97875 vs $4.00 per 1M tokens).

Which model is cheaper to use through an API?

DeepSeek V4 Pro 0423 is about 4.1× cheaper on a blended 3:1 input/output basis ($0.97875 vs $4.00 per 1M tokens).

Which model supports more context?

The published context windows are close enough that this page does not treat the difference as a material advantage.

Can I switch between Claude Sonnet 5 and DeepSeek V4 Pro 0423?

Yes. Use the model selector on this page to open any current Writingmate model comparison. You can also run the same prompt with both models in Writingmate.