Last verified 2026-05-15 (left) · 2026-05-15 (right)

DeepSeek V4 Flash vs GPT-5.4 nano — Pricing & Capability Comparison

DeepSeek V4 Flash charges $0.14 per million input tokens and $0.28 per million output tokens. GPT-5.4 nano comes in at $0.20 / $1.25. Context windows span 1M vs 400K tokens respectively.

TL;DR — Quick Comparison

✓DeepSeek V4 Flash is cheaper overall: $0.42 per 1M tokens (in+out) vs $1.45 for GPT-5.4 nano — saves $1.03 per 1M tokens
✓Input pricing: DeepSeek V4 Flash $0.14/1M vs GPT-5.4 nano $0.20/1M
✓Output pricing: DeepSeek V4 Flash $0.28/1M vs GPT-5.4 nano $1.25/1M
✓Context window: DeepSeek V4 Flash offers more (1M vs 400K)
✓Use our calculator below to estimate costs for your specific usage pattern

Input price (per 1M)

DeepSeek V4 Flash

$0.14

GPT-5.4 nano

$0.20

DeepSeek V4 Flash leads here

Output price (per 1M)

DeepSeek V4 Flash

$0.28

GPT-5.4 nano

$1.25

DeepSeek V4 Flash leads here

Context window

DeepSeek V4 Flash

1,000,000 tokens

GPT-5.4 nano

400,000 tokens

DeepSeek V4 Flash leads here

Cached input

DeepSeek V4 Flash

$0.003

GPT-5.4 nano

$0.020

DeepSeek V4 Flash leads here

Which one should you choose?

Skip the spreadsheet if you just need the practical takeaway. Use these rules when deciding between DeepSeek V4 Flash and GPT-5.4 nano.

Choose DeepSeek V4 Flash if input tokens dominate your bill

DeepSeek V4 Flash has the lower input rate, which usually matters most for chat, RAG, classification, and long-prompt workflows where prompt volume stays much larger than generated output.

Choose DeepSeek V4 Flash if you generate long answers

DeepSeek V4 Flash is cheaper on output tokens, so it tends to win for report generation, coding assistance, reasoning traces, and any workflow where completions are long.

Choose DeepSeek V4 Flash if context size is the blocker

DeepSeek V4 Flash offers the larger published context window, which is more important than small pricing differences when you need to fit large files, long chats, or multi-document prompts into one request.

Cost comparison for 10K-token workloads

Side-by-side pricing for identical workloads (10,000 total tokens per request) across different distributions.

Scenario	DeepSeek V4 Flash	GPT-5.4 nano	DeepSeek V4 Flash cached	GPT-5.4 nano cached
Balanced conversation 50% input · 50% output	$0.0021	$0.0073	$0.0014	$0.0064
Input-heavy workflow 80% input · 20% output	$0.0017	$0.0041	$0.0006	$0.0027
Generation heavy 30% input · 70% output	$0.0024	$0.0094	$0.0020	$0.0088
Cached system prompt 90% cached input · 10% fresh output	$0.0015	$0.0030	$0.0003	$0.0014

Frequently asked questions

Which is cheaper: DeepSeek V4 Flash or GPT-5.4 nano?

DeepSeek V4 Flash is cheaper for input tokens at $0.14 per 1M tokens compared to $0.20. For output, DeepSeek V4 Flash costs $0.28 per 1M tokens versus $1.25 for GPT-5.4 nano.

What is the cost per 1M tokens for DeepSeek V4 Flash?

DeepSeek V4 Flash pricing: $0.14 per 1M input tokens and $0.28 per 1M output tokens. Context window: 1,000,000 tokens.

What is the cost per 1M tokens for GPT-5.4 nano?

GPT-5.4 nano pricing: $0.20 per 1M input tokens and $1.25 per 1M output tokens. Context window: 400,000 tokens.

How much does it cost per 1K tokens?

Per 1K tokens: DeepSeek V4 Flash costs $0.0001 input / $0.0003 output. GPT-5.4 nano costs $0.0002 input / $0.0013 output. This is useful for calculating small-scale usage costs.

Which model supports a larger context window?

DeepSeek V4 Flash offers 1,000,000 tokens (1M) versus 400K for GPT-5.4 nano.

What is the estimated monthly cost for typical usage?

For a typical workload of 10M input + 2M output tokens per month: DeepSeek V4 Flash would cost approximately $1.96, while GPT-5.4 nano would cost $4.50. DeepSeek V4 Flash is more economical for this usage pattern.

Do these models support prompt caching?

DeepSeek V4 Flash supports prompt caching at $0.003 per 1M cached tokens, reducing costs for repeated context by up to 98%. GPT-5.4 nano supports caching at $0.020 per 1M tokens, saving up to 90%.

Which model is best for my use case?

Choose DeepSeek V4 Flash for cost-sensitive applications with high input volume. Choose DeepSeek V4 Flash if you need 1M context for long documents or conversations. Consider prompt caching if you have repeated context. Use our token calculator to model your specific usage pattern.