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TokenMath.net
Updated 2026-09-22 11:16 UTC
Head-to-Head Specification Battle

DeepSeek-V4.1-Flash vs DeepSeek-V3 (Legacy API Alias)

Side-by-side technical and economic comparison between DeepSeek's DeepSeek-V4.1-Flash and DeepSeek's DeepSeek-V3 (Legacy API Alias).

Endpoint Availability & Transition Notice

DeepSeek-V3 (Legacy API Alias): Classified as a Legacy Reference model (Legacy Reference (API Aliased)).

Core Technical & Pricing Comparison
MetricDeepSeek-V4.1-FlashDeepSeek-V3 (Legacy API Alias)Advantage
Provider OrganizationDeepSeekDeepSeek
Standard Input / 1M$0.30$0.14DeepSeek-V3 (Legacy API Alias) (53% lower)
Cached Input / 1M$0.006$0.014DeepSeek-V4.1-Flash lower
Output / 1M$1.20$0.28DeepSeek-V3 (Legacy API Alias) lower
Context Window1.05M128kDeepSeek-V4.1-Flash (1.05M)
Max Generation Tokens384k8.2kDeepSeek-V4.1-Flash
Tokenizer FamilyDeepSeek Byte-Level BPE (100k vocabulary)DeepSeek Byte-level BPE (~128k vocabulary)

Interactive Side-by-Side Cost Simulator

Live Delta
Input Tokens / Req2,500
Output Tokens / Req800
Daily Requests10,000
DeepSeek-V4.1-Flash
$402.75 / month
$0.00134 / request
DeepSeek-V3 (Legacy API Alias)LOWER COST
$124.95 / month
$0.00042 / request
Selecting DeepSeek-V3 (Legacy API Alias) saves $277.80 / month (69.0% savings) over DeepSeek-V4.1-Flash.

When to Choose DeepSeek-V4.1-Flash

Opt for DeepSeek-V4.1-Flash when your engineering requirements prioritize DeepSeek's ecosystem, specific tokenizer efficiencies (Calibrated DeepSeek Tokenizer (±3%)), or when your expected prompt-to-completion ratios favor its $0.3/M input rate.

When to Choose DeepSeek-V3 (Legacy API Alias)

Opt for DeepSeek-V3 (Legacy API Alias) when looking for DeepSeek's tooling integration, specific context window depth (128k tokens), or when output generation volume favors its $0.28/M rate.