DeepSeek-V4-Flash vs GPT-5.6 Luna
Pricing & Specs

DeepSeek vs OpenAI, side by side from a live registry. Specs below, then benchmark both on your own task.

$1.32
DeepSeek-V4-Flash output / 1M
$1.2
GPT-5.6 Luna output / 1M
1M / 1.05M
context windows

TL;DR: On a typical task (1K input + 500 output tokens), GPT-5.6 Luna is about 1.4x cheaper than DeepSeek-V4-Flash. But per-token price is not cost per result: a cheaper model that needs more tokens, retries, or hand-holding can end up more expensive on your workload. The specs below are facts; which one is better at YOUR task is measurable, not guessable.

API Pricing: DeepSeek-V4-Flash vs GPT-5.6 Luna

TokensDeepSeek-V4-FlashGPT-5.6 Luna
Input$0.44 / 1M$0.2 / 1M
Output$1.32 / 1M$1.2 / 1M
Cached input$0.014 / 1M$0.02 / 1M

What that means in practice (1K input + 500 output tokens)

1x One typical task: $0.0011 on DeepSeek-V4-Flash vs $0.0008 on GPT-5.6 Luna
1K 1,000 runs: $1.10 vs $0.80
💡 Real cost depends on how verbose each model is on YOUR prompts. Benchmark to measure actual tokens, not estimates.

Specs Compared

SpecDeepSeek-V4-FlashGPT-5.6 Luna
Context window1M tokens1.05M tokens
Max output tokens384K tokens128K tokens
Input modalitiestexttext, image
Knowledge cutoff-February 16, 2026
Latency (measured)--
Reasoning modelYesYes
Tool / function callingYesYes
JSON modeYesYes
Prompt cachingYesYes

When to Choose Which

High volume on a budget: start with GPT-5.6 Luna; only pay for DeepSeek-V4-Flash if the benchmark shows a quality gap that matters.
Everything else: the honest answer is to benchmark both on your actual task. Quality differences are task-specific and shift with every release.

FAQ

Which is cheaper, DeepSeek-V4-Flash or GPT-5.6 Luna?

DeepSeek-V4-Flash costs $0.44/$1.32 per 1M input/output tokens; GPT-5.6 Luna costs $0.2/$1.2. On a typical task (1K input + 500 output tokens), GPT-5.6 Luna is about 1.4x cheaper than DeepSeek-V4-Flash.

Which has the bigger context window, DeepSeek-V4-Flash or GPT-5.6 Luna?

DeepSeek-V4-Flash has a 1M-token context window; GPT-5.6 Luna has 1.05M tokens.

Is DeepSeek-V4-Flash better than GPT-5.6 Luna?

It depends on the task. Generic leaderboards won't tell you which one wins on YOUR workload. OpenMark lets you benchmark DeepSeek-V4-Flash and GPT-5.6 Luna head to head on your own task with real API calls, no API keys needed, free tier available.

DeepSeek-V4-Flash or GPT-5.6 Luna for YOUR Task?

Spec tables can't answer that. Run both head to head on your actual workload:
real API calls, ranked results with accuracy, cost, and latency. Free tier available.

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