LLM Reference

Claude Fable 5 vs DeepSeek V4 Flash

Claude Fable 5 (2026) and DeepSeek V4 Flash (2026) are frontier-tier reasoning models from Anthropic and DeepSeek. Claude Fable 5 ships a 1m-token context window, while DeepSeek V4 Flash ships a 1m-token context window. On SWE-bench Verified, Claude Fable 5 leads by 17 pts. On pricing, DeepSeek V4 Flash costs $0.10/1M input tokens versus $10/1M for the alternative. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.

DeepSeek V4 Flash is ~10073% cheaper at $0.10/1M; pay for Claude Fable 5 only for vision-heavy evaluation.

Decision scorecard

Local evidence first
SignalClaude Fable 5DeepSeek V4 Flash
Best forreasoning-heavy apps, multimodal apps, and tool-calling agentsreasoning-heavy apps, tool-calling agents, and long-context analysis
Decision fitCoding, RAG, and AgentsCoding, RAG, and Agents
Context window1m1m
Cheapest output$50/1M tokens$0.20/1M tokens
Provider routes4 tracked5 tracked
Shared benchmarksSWE-bench Verified leader2 rows

Decision tradeoffs

Choose Claude Fable 5 when...
  • Claude Fable 5 holds a shared-benchmark lead on SWE-bench Verified, ahead by 17 points.
  • Claude Fable 5 uniquely exposes Vision and Multimodal in local model data.
  • Local decision data tags Claude Fable 5 for Coding, RAG, and Agents.
Choose DeepSeek V4 Flash when...
  • DeepSeek V4 Flash has the lower cheapest tracked output price at $0.20/1M tokens.
  • DeepSeek V4 Flash has broader tracked provider coverage for fallback and procurement flexibility.
  • Local decision data tags DeepSeek V4 Flash for Coding, RAG, and Agents.

Monthly cost at traffic

Estimate token spend from the cheapest tracked input and output route or tier on this page.

Lower estimate DeepSeek V4 Flash

Claude Fable 5

$20,500

Cheapest tracked route/tier: Anthropic

DeepSeek V4 Flash

$128

Cheapest tracked route/tier: OpenRouter

Estimated monthly gap: $20,372. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

Claude Fable 5 -> DeepSeek V4 Flash
  • Provider overlap exists on Microsoft Foundry; start route-level A/B tests there.
  • DeepSeek V4 Flash is $49.80/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
  • Check replacement coverage for Vision and Multimodal before moving production traffic.
DeepSeek V4 Flash -> Claude Fable 5
  • Provider overlap exists on Microsoft Foundry; start route-level A/B tests there.
  • Claude Fable 5 is $49.80/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • Claude Fable 5 adds Vision and Multimodal in local capability data.

Specs

Specification
Released2026-06-092026-04-24
Context window1m1m
Parameters284B
Architecturedecoder onlymixture of experts
LicenseProprietaryMIT(OSI)
OpennessProprietaryOpen source
Commercial useCommercial use with conditionsCommercial use allowed
Knowledge cutoff--

Pricing and availability

Pricing attributeClaude Fable 5DeepSeek V4 Flash
Input price$10/1M tokens$0.10/1M tokens
Output price$50/1M tokens$0.20/1M tokens
Providers

Capabilities

CapabilityClaude Fable 5DeepSeek V4 Flash
VisionYesNo
MultimodalYesNo
ReasoningYesYes
Function callingYesYes
Tool useYesYes
Structured outputsYesYes
Code executionNoNo
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

BenchmarkClaude Fable 5DeepSeek V4 Flash
SWE-bench Verified96.079.0
SWE-bench Pro80.352.6

Deep dive

On shared benchmark coverage, SWE-bench Verified has Claude Fable 5 at 96 and DeepSeek V4 Flash at 79, with Claude Fable 5 ahead by 17 points; SWE-bench Pro has Claude Fable 5 at 80.3 and DeepSeek V4 Flash at 52.6, with Claude Fable 5 ahead by 27.7 points. The largest visible gap is 27.7 points on SWE-bench Pro, which matters most when that benchmark mirrors your workload. Treat isolated benchmark wins as directional, because provider routing, prompt style, and tool access can move real application results.

The capability footprint differs most on vision: Claude Fable 5 and multimodal input: Claude Fable 5. Both models share reasoning mode, function calling, tool use, and structured outputs, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.

For cost, Claude Fable 5 lists $10/1M input and $50/1M output tokens on the cheapest tracked provider, while DeepSeek V4 Flash lists $0.10/1M input and $0.20/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts DeepSeek V4 Flash lower by about $21.87 per million blended tokens. Availability is 4 providers versus 5, so concentration risk also matters.

Choose Claude Fable 5 when vision-heavy evaluation are central to the workload. Choose DeepSeek V4 Flash when provider fit, lower input-token cost, and broader provider choice are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship.

FAQ

Which has a larger context window, Claude Fable 5 or DeepSeek V4 Flash?

Claude Fable 5 supports 1m tokens, while DeepSeek V4 Flash supports 1m tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.

Which is cheaper, Claude Fable 5 or DeepSeek V4 Flash?

DeepSeek V4 Flash is cheaper on tracked token pricing. Claude Fable 5 costs $10/1M input and $50/1M output tokens. DeepSeek V4 Flash costs $0.10/1M input and $0.20/1M output tokens. Provider discounts or batch pricing can still change the final bill.

Is Claude Fable 5 or DeepSeek V4 Flash open source?

Claude Fable 5 is listed under Proprietary. DeepSeek V4 Flash is listed under MIT. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.

Which is better for vision, Claude Fable 5 or DeepSeek V4 Flash?

Claude Fable 5 has the clearer documented vision signal in this comparison. If vision is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Which is better for multimodal input, Claude Fable 5 or DeepSeek V4 Flash?

Claude Fable 5 has the clearer documented multimodal input signal in this comparison. If multimodal input is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Where can I run Claude Fable 5 and DeepSeek V4 Flash?

Claude Fable 5 is available on Anthropic, AWS Bedrock, GCP Vertex AI, and Microsoft Foundry. DeepSeek V4 Flash is available on DeepSeek Platform, OpenRouter, Microsoft Foundry, Vercel AI Gateway, and Novita AI. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-06-09. Data sourced from public model cards and provider documentation.