AI model comparison

Step 5 Preview vs DeepSeek V4 Flash 0731

Pricing, context window, benchmarks, and features compared side by side. Or skip the guesswork and send one prompt to both.

Step 5 Preview is StepFun's flagship model for agentic work, built on a sparse Mixture-of-Experts architecture (27B active / 600B total parameters).

Input / 1M
$1
Output / 1M
$2.70
Context
1M

DeepSeek V4 Flash 0731 is a sparse mixture-of-experts model from DeepSeek, with 13B active parameters out of 284B total.

Input / 1M
$0.00
Output / 1M
$1.28
Context
1.05M

At a glance

Quick verdict

How the two models stack up on the things people ask about most.

Lower price

deepseek logo

DeepSeek V4 Flash 0731

5.2x cheaper for a typical chat

Higher intelligence score

Tie

Not enough benchmark data

Larger context window

deepseek logo

DeepSeek V4 Flash 0731

1.05M vs 1M tokens

Newer release

stepfun logo

Step 5 Preview

Released October 8, 2026

Benchmarks

Benchmark scores

Independent scores from Artificial Analysis. Higher is better.

Intelligence index

stepfun logoStep 5 PreviewNot available
deepseek logoDeepSeek V4 Flash 073134.3

Coding index

stepfun logoStep 5 PreviewNot available
deepseek logoDeepSeek V4 Flash 073169.1

Agentic index

stepfun logoStep 5 PreviewNot available
deepseek logoDeepSeek V4 Flash 073141

Pricing

Step 5 Preview vs DeepSeek V4 Flash 0731 API pricing

Per-token API rates. Cheaper option highlighted.

Metricstepfun logoStep 5 Previewdeepseek logoDeepSeek V4 Flash 0731
Input tokensPer 1M tokens$1$0.00
Output tokensPer 1M tokens$2.70$1.28
Cached input (read)Per 1M tokens$0.05$0.00
Cache writePer 1M tokensNot availableNot available

What it costs in practice

Estimated cost per 1,000 requests at standard rates. Coding and long-document figures also show the cost when the input is already cached.

Chat message

2K in, 500 out

stepfun logoStep 5 Preview$3.35
deepseek logoDeepSeek V4 Flash 0731$0.65

Coding task

30K in, 4K out

stepfun logoStep 5 Preview$40.80$12.30 cached
deepseek logoDeepSeek V4 Flash 0731$5.26$5.26 cached

Long document summary

150K in, 2K out

stepfun logoStep 5 Preview$155.40$12.90 cached
deepseek logoDeepSeek V4 Flash 0731$3.28$3.28 cached

Specs

Context window and capabilities

How much each model can read, how much it can write, and what it accepts as input.

Metricstepfun logoStep 5 Previewdeepseek logoDeepSeek V4 Flash 0731
Context window1M tokens1.05M tokens
Max output64K tokens944K tokens
Input typesImage, Text, VideoText
Output typesTextText
Reasoning effort levelsHigh, Medium, LowMax, High, Low
Default reasoning effortMediumHigh
Release dateOctober 8, 2026July 31, 2026

Features

Supported features

API features available for each model.

Metricstepfun logoStep 5 Previewdeepseek logoDeepSeek V4 Flash 0731
Tool callingSupportedSupported
Structured outputsSupportedSupported
JSON modeSupportedSupported
ReasoningSupportedSupported
TemperatureSupportedSupported
Stop sequencesSupportedSupported
Deterministic seedNot supportedSupported
Verbosity controlNot supportedNot supported

Our take

DeepSeek V4 Flash 0731 is 5.2x cheaper for a typical chat. DeepSeek V4 Flash 0731 has the larger context window (1.05M vs 1M tokens). The right pick depends on your workload, so the quickest way to settle it is to send the same prompt to both and compare.

FAQ

Frequently asked questions

Is Step 5 Preview or DeepSeek V4 Flash 0731 cheaper?

DeepSeek V4 Flash 0731 is cheaper for a typical chat (2K input tokens and 500 output tokens). DeepSeek V4 Flash 0731 costs $0.00 per 1M input tokens and $1.28 per 1M output tokens, while Step 5 Preview costs $1 per 1M input tokens and $2.70 per 1M output tokens.

Which has a bigger context window, Step 5 Preview or DeepSeek V4 Flash 0731?

DeepSeek V4 Flash 0731 supports up to 1.05M tokens of context, compared with 1M for Step 5 Preview.

Can I use Step 5 Preview and DeepSeek V4 Flash 0731 at the same time?

Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see Step 5 Preview and DeepSeek V4 Flash 0731 answer side by side and keep the better response.

stepfun logodeepseek logo

Why choose? Ask both.

Send one prompt to Step 5 Preview and DeepSeek V4 Flash 0731 at the same time. Compare the answers side by side and keep the best one.