Compare AI models

API pricing
Input price
$2.00—
Output price
$10.00—
Cached input price
$0.20—
Cheapest input
$2.00Amazon Bedrock$0.003Relace
Cheapest output
$10.00Amazon Bedrock$0.18Decart
Benchmarks
BullshitBench v2
80%57%
Terminal-Bench 4.0
12.42%31.2%
Terminal-Bench 2.1
80.4%90.6%
Humanity's Last Exam · no tools
43.2%36.8%
Humanity's Last Exam · with tools
57.4%63.9%
Overview
CompanyAnthropicDeepSeek
Release dateJun 30 2026Sep 10 2026
AccessClosedOpen Weight
Model detailsView modelView model

Frequently asked questions

DeepSeek-V4.1-Flash leads Claude Sonnet 5 on 3 of the 5 benchmarks they both report (BullshitBench v2, Terminal-Bench 4.0, Terminal-Bench 2.1, Humanity's Last Exam). Only Claude Sonnet 5 has a verified first-party API price: $2.00 per million input tokens and $10.00 per million output tokens. No pay-as-you-go API rate is tracked for DeepSeek-V4.1-Flash. Claude Sonnet 5 shipped 72 days before DeepSeek-V4.1-Flash, so benchmark comparisons should account for the intervening progress.

Claude Sonnet 5 is closed, while DeepSeek-V4.1-Flash is open weight.

On BullshitBench v2, Claude Sonnet 5 leads at 80% vs DeepSeek-V4.1-Flash at 57%. On Terminal-Bench 4.0, DeepSeek-V4.1-Flash leads at 31.2% vs Claude Sonnet 5 at 12.42%. On Terminal-Bench 2.1, DeepSeek-V4.1-Flash leads at 90.6% vs Claude Sonnet 5 at 80.4%. On Humanity's Last Exam · no tools, Claude Sonnet 5 leads at 43.2% vs DeepSeek-V4.1-Flash at 36.8%. On Humanity's Last Exam · with tools, DeepSeek-V4.1-Flash leads at 63.9% vs Claude Sonnet 5 at 57.4%.