AI model comparison
Compare recorded price, context, output limits, speed, latency, capabilities, and input/output support. Every missing value stays visible, and unsourced benchmarks are excluded.
Claude 3.5 Sonnet and DeepSeek V4 Flash 0731 both come up when teams are choosing a model for production work, and the honest answer usually depends on your workload rather than a leaderboard. This page puts their published specifications side by side — context window, token pricing, supported inputs and outputs — so you can see where they actually differ.
Anthropic
The 2024 Sonnet that set the standard for practical coding work — now well behind the current Claude line at identical pricing.
Accepts
Produces
DeepSeek
Official DeepSeek V4 Flash release with enhanced agentic capabilities and integrated DSpark speculative decoding
Accepts
Produces
At a glance
This is a directional summary of the values recorded in this directory—not a universal quality verdict. Test the finalists on your own prompts before committing.
Where Claude 3.5 Sonnet leads in recorded data
No complete recorded factor currently favors this model. That does not establish lower real-world quality.
Where DeepSeek V4 Flash 0731 leads in recorded data
Context capacity
Higher listed limit
Claude 3.5 Sonnet:200K
DeepSeek V4 Flash 0731:1M
DeepSeek V4 Flash 0731
Maximum output
Higher listed limit
Claude 3.5 Sonnet:8.2K
DeepSeek V4 Flash 0731:384K
DeepSeek V4 Flash 0731
Input price
Lower recorded price
Claude 3.5 Sonnet:$3.00
DeepSeek V4 Flash 0731:$0.16
DeepSeek V4 Flash 0731
Output price
Lower recorded price
Claude 3.5 Sonnet:$15.00
DeepSeek V4 Flash 0731:$0.40
DeepSeek V4 Flash 0731
Output speed
Higher recorded throughput
Claude 3.5 Sonnet:78 t/s
DeepSeek V4 Flash 0731:—
No complete comparison
Time to first token
Lower recorded latency
Claude 3.5 Sonnet:0.60s
DeepSeek V4 Flash 0731:—
No complete comparison
Intelligence Index
Higher directory index
Claude 3.5 Sonnet:80.1
DeepSeek V4 Flash 0731:—
No complete comparison
Evidence
A score appears only when both records include a verified source. It is not treated as a universal ranking.
Specifications
| Specification | Claude 3.5 Sonnet | DeepSeek V4 Flash 0731 |
|---|---|---|
| Provider | Anthropic | DeepSeek |
| Model family | Claude 3.5 | deepseek-flash |
| Accepted inputs | text, image | text |
| Produced outputs | text | text |
| Context window | 200K | 1MRecorded lead |
| Max output | 8.2K | 384KRecorded lead |
| Intelligence Index | 80.1 | — |
| Input price / 1M | $3.00 | $0.16Recorded lead |
| Output price / 1M | $15.00 | $0.40Recorded lead |
| Output speed | 78 t/s | — |
| Time to first token | 0.60s | — |
| Reasoning mode | Documented | Documented |
| Tool calling | Documented | Documented |
| Image input | Documented | Not documented |
| Audio input | Not documented | Not documented |
| Structured output | Documented | Documented |
| License | Proprietary | Open weights |
| Released | Jun 20, 2024 | Jul 31, 2026 |
Workload guidance
On the published numbers, DeepSeek V4 Flash 0731 accepts the larger context window and DeepSeek V4 Flash 0731 is cheaper per input token. Which matters more depends on whether your bottleneck is document size or spend — the table above has the exact figures.
Provenance
Prices and hosted performance can change. SyncDev records source references and clearly separates documented specifications from measured values; confirm commercial terms with the provider before deployment.
Claude 3.5 Sonnet
Anthropic · model record and recorded source
DeepSeek V4 Flash 0731
DeepSeek · model record and recorded source
Choose any two approved model records and review them with the same evidence rules.