o3 vs DeepSeek-V3: Detailed Comparison
Choosing between o3 (OpenAI) and
DeepSeek-V3 (DeepSeek) comes down to three things:
per-token pricing, context window, and which capability matters most for your workload.
o3 costs $2.00/M input vs
$0.27/M for DeepSeek-V3;
context windows are 200K vs
128K tokens. Detailed breakdown below.
Side-by-side specs
| Spec | o3 | DeepSeek-V3 |
|---|
| Provider | OpenAI | DeepSeek |
|---|
| Released | 2025-04-16 | 2024-12-26 |
|---|
| Input price |
$2.00/M |
$0.27/M |
| Output price |
$8.00/M |
$1.10/M |
| Cached input |
$0.5000/M |
$0.0700/M |
| Context window |
200K |
128K |
| Max output |
100K |
8K |
| Modalities |
text image |
text |
| Tokenizer |
o200k_base |
deepseek |
Capability matrix
| Capability | o3 | DeepSeek-V3 |
|---|
| function calling |
Yes |
Yes |
| json mode |
Yes |
Yes |
| vision |
Yes |
No |
| reasoning |
Yes |
No |
| streaming |
No |
Yes |
Benchmark comparison
Higher is better for all benchmarks shown.
Per-call cost on typical workloads
| Workload (in/out tokens) | o3 | DeepSeek-V3 | Cheaper by |
|---|
| Standard chat (1K / 500) |
$0.006000 |
$0.000820 |
DeepSeek-V3 by $0.005180 |
| RAG (4K / 500) |
$0.012000 |
$0.001630 |
DeepSeek-V3 by $0.010370 |
| Long doc (20K / 1K) |
$0.048000 |
$0.006500 |
DeepSeek-V3 by $0.041500 |
| Very long context (100K / 2K) |
$0.212000 |
$0.028650 |
DeepSeek-V3 by $0.183350 |
When to choose o3 over DeepSeek-V3
- Larger context window (200K vs 128K) — relevant when whole documents or long histories must fit in a single call.
- Supports vision — DeepSeek-V3 does not.
- Supports reasoning — DeepSeek-V3 does not.
When to choose DeepSeek-V3 over o3
- Per-token input cost is 87% lower than o3.
- Supports streaming — o3 does not.
Related comparisons