How much does Step 3.5 Flash 2603 cost?

The lowest price for Step 3.5 Flash 2603 is $0.30 /1M, at EmpirioLabs AI.

What is Step 3.5 Flash 2603's context window?

Step 3.5 Flash 2603 reads up to 256K tokens per request.

We have not found Step 3.5 Flash 2603's weights published by its maker.

1 API providers serve Step 3.5 Flash 2603. Compare their prices above, or open a provider to see everything it offers.

Step 3.5 Flash 2603 is a text model by StepFun. One provider serves it: EmpirioLabs AI, at $0.30 /1M.

Lowest price$0.30/1Mat EmpirioLabs AI

Maker's price—The maker does not sell it

Providers1

Context256K

Against the 737 text models on the site priced the same way.

Cheap for its class: at $0.30 /1M, its lowest price undercuts 76% of comparable models (median $1.10).
Its 256K-token context window is larger than 38% of them (median 262K), about 380 pages of text.
1 providers serve it; 0% of comparable models have fewer.

Every provider's list price, read from its own price page or API. A price marked “from” changes with context length, resolution or mode.

Provider	Input	Output	Prompt caching	Context
EmpirioLabs AI	$0.10/1M	$0.30/1M	$0.02/1M	256K

Prices in US dollars, updated daily from each provider. Prices last checked Oct 25, 2026.

Same kind of model from other makers, at a similar price.

Model	Lowest price	Context	Arena	Providers
Step 3.5 Flash 2603this model	$0.30/1M	256K	—	1
GLM-5.3-Flash	$0.20/1M	1.05M	1608	45
Qwen3.8 27B	$0.50/1M	262K	1591	33
GPT-6 Luna	$0.40/1M	1.05M	1578	28
Claude Haiku 5.5	$0.30/1M	1M	1585	27
MiMo-V2.6-Pro	$0.696/1M	1.05M	1625	21
Qwen3.8 Flash Next	$0.376/1M	262K	1628	5
DeepSeek V4 Flash	$0.17/1M	1.05M	—	26
DeepSeek V4 Flash Vision Exp	$0.294/1M	1.05M	—	26