Compare AI models

API pricing
Input price
$3.00—
Output price
$15.00—
Cached input price
$0.30—
Cheapest input
$3.00Amazon Bedrock$0.0348Baidu
Cheapest output
$15.00Amazon Bedrock$0.1392Baidu
Benchmarks
BullshitBench v2
79%57%
GPQA Diamond
83.4%90.9%
Overview
CompanyAnthropicDeepSeek
Release dateSep 29 2025Sep 10 2026
AccessClosedOpen Weight
Model detailsView modelView model

Frequently asked questions

Claude Sonnet 4.5 and DeepSeek-V4.1-Flash are evenly matched across the 2 benchmarks they both report (BullshitBench v2, GPQA Diamond). Only Claude Sonnet 4.5 has a verified first-party API price: $3.00 per million input tokens and $15.00 per million output tokens. No pay-as-you-go API rate is tracked for DeepSeek-V4.1-Flash. Claude Sonnet 4.5 shipped 346 days before DeepSeek-V4.1-Flash, so benchmark comparisons should account for the intervening progress.

Claude Sonnet 4.5 is closed, while DeepSeek-V4.1-Flash is open weight.

On BullshitBench v2, Claude Sonnet 4.5 leads at 79% vs DeepSeek-V4.1-Flash at 57%. On GPQA Diamond, DeepSeek-V4.1-Flash leads at 90.9% vs Claude Sonnet 4.5 at 83.4%.