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Claude Opus 5 vs DeepSeek V4.1 Flash: pricing and benchmarks

DeepSeek V4.1 Flash is 94% cheaper on input tokens ($0.30 vs $5.00 per 1M). DeepSeek V4.1 Flash is 95% cheaper on output tokens ($1.20 vs $25.00 per 1M). On our document Q&A workload (50,000 questions a month), DeepSeek V4.1 Flash costs $156.00 a month versus $2,750 for Claude Opus 5, 94% less. Epoch AI has not published a capability index score for DeepSeek V4.1 Flash yet.

Prices verified September 14, 2026.

Which should you choose?

Overall capability
Too close to call

Epoch AI has not published a capability index score for DeepSeek V4.1 Flash yet.

Price
DeepSeek V4.1 Flash

DeepSeek V4.1 Flash costs $0.525 per 1M tokens (3:1 input-to-output mix) vs $10.00 for Claude Opus 5, 95% less.

Pricing and specs

Claude Opus 5DeepSeek V4.1 Flash
ProviderAnthropicDeepSeek
API model IDclaude-opus-5deepseek-flash
Input / 1M tokens$5.00$0.30
Cached input / 1M tokens$0.50$0.006
Output / 1M tokens$25.00$1.20
Long-context rates
Context window1M tokens1M tokens
Max output128K tokens384K tokens
Batch discount50% off

Benchmarks

Claude Opus 5DeepSeek V4.1 Flash
Epoch Capabilities Index162.3
GPQA Diamond· Science reasoning91.8%
FrontierMath (Tiers 1–3)· Advanced math85.6%
SimpleQA Verified· Factual accuracy59.9%
ARC-AGI-2· Abstract reasoning90.4%
DeepSWE· Coding73.6%
APEX-Agents· Agentic work43.5%

Source: Epoch AI, best recorded result per model (CC BY 4.0). A dash means no published score. See all benchmarks

Monthly cost for real workloads

WorkloadClaude Opus 5DeepSeek V4.1 FlashDifference
Support chatbot
100,000 replies a month, ~1,500 input tokens (system prompt + history) and ~400 output tokens each.
$1,750$93.00DeepSeek V4.1 Flash 95% cheaper
Document Q&A (RAG)
50,000 questions a month with ~8,000 tokens of retrieved context and ~600 output tokens each.
$2,750$156.00DeepSeek V4.1 Flash 94% cheaper
Coding agent
10,000 agent steps a month, ~40,000 input tokens each (70% read from the prompt cache) and ~2,000 output tokens.
$1,240$61.68DeepSeek V4.1 Flash 95% cheaper

Estimates use standard list prices and ignore cache-write surcharges. Different tokenizers can count the same text differently, so test with your own prompts.

Claude Opus 5 vs DeepSeek V4.1 Flash cost calculator

Standard-tier list prices. Long-context rates apply automatically where the provider publishes a threshold. Excludes cache-write surcharges, taxes, batch and volume discounts.

Claude Opus 5 pricing notes

Anthropic’s model for complex agentic coding and enterprise work.

  • Cache writes cost $6.25 (5-minute cache) or $10 (1-hour cache) per 1M tokens.
  • Uses Anthropic’s newer tokenizer, which produces roughly 30% more tokens for the same text.
  • US-only inference (inference_geo: "us") costs 1.1x.
Anthropic official pricing ↗

DeepSeek V4.1 Flash pricing notes

DeepSeek’s low-cost model with thinking and non-thinking modes, tool calls and vision input.

  • Prices shown are peak rates. Off-peak rates are half: peak hours are 01:00–04:00 and 06:00–10:00 UTC, Monday to Friday.
  • Compatible with both OpenAI-format and Anthropic-format APIs.
DeepSeek official pricing ↗

Frequently asked questions

Is Claude Opus 5 cheaper than DeepSeek V4.1 Flash?
DeepSeek V4.1 Flash is 94% cheaper on input tokens ($0.30 vs $5.00 per 1M). DeepSeek V4.1 Flash is 95% cheaper on output tokens ($1.20 vs $25.00 per 1M). On our document Q&A workload (50,000 questions a month), DeepSeek V4.1 Flash costs $156.00 a month versus $2,750 for Claude Opus 5, 94% less.
Which is more capable, Claude Opus 5 or DeepSeek V4.1 Flash?
Epoch AI has not published a capability index score for DeepSeek V4.1 Flash yet.
How much does Claude Opus 5 cost per 1M tokens?
Claude Opus 5 costs $5.00 per 1M input tokens and $25.00 per 1M output tokens, and $0.50 per 1M cached input tokens on Anthropic’s standard tier.
How much does DeepSeek V4.1 Flash cost per 1M tokens?
DeepSeek V4.1 Flash costs $0.30 per 1M input tokens and $1.20 per 1M output tokens, and $0.006 per 1M cached input tokens on DeepSeek’s standard tier.
Which has the larger context window, Claude Opus 5 or DeepSeek V4.1 Flash?
Both offer a 1M-token context window.

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