API cost decision in 10 seconds

🔥DeepSeek V4 Flash 0423 vs Solar Pro 4

Pick Solar Pro 4 for lower cost; pick DeepSeek V4 Flash 0423 only if the larger context window matters more.

Page updated: 2026-08-23T12:07:48Z Data confirmed: 2026-08-23T12:07:48Z Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick Solar Pro 4 for lower cost; pick DeepSeek V4 Flash 0423 only if the larger context window matters more.

On the standard 1M input plus 500K output workload, Solar Pro 4 is estimated at $0.09 vs $0.1 for DeepSeek V4 Flash 0423, saving $0.01 (10.5% lower).

Cost-first pickSolar Pro 4

Context-first pickDeepSeek V4 Flash 0423

Sample savings$0.0110.5%

10x traffic gap$0.11

DeepSeek V4 Flash 0423 has more context, but Solar Pro 4 saves $0.01 on the standard workload. At 10x that traffic, the same price gap is about $0.11. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

Cost winner changes by workload shape: input-heavy / RAG favors Solar Pro 4, balanced workload favors Solar Pro 4, and output-heavy chatbot favors DeepSeek V4 Flash 0423.

Workload shape	Token mix	Better pick	DeepSeek V4 Flash 0423	Solar Pro 4
Input-heavy / RAG	5M input + 500K output	Solar Pro 4	$0.3	$0.21
Balanced workload	1M input + 1M output	Solar Pro 4	$0.15	$0.15
Output-heavy chatbot	1M input + 5M output	DeepSeek V4 Flash 0423	$0.55	$0.63

Cheaper input Solar Pro 4 $0.0503 vs $0.03 / 1M

Solar Pro 4 is $0.02 cheaper per 1M input tokens (40.4% lower; 1.68x difference).

Cheaper output DeepSeek V4 Flash 0423 $0.1005 vs $0.12 / 1M

DeepSeek V4 Flash 0423 is $0.02 cheaper per 1M output tokens (16.2% lower; 1.19x difference).

Larger context DeepSeek V4 Flash 0423 1.05M vs 524.29K

DeepSeek V4 Flash 0423 has 524.29K more context (2x larger).

Sample workload Solar Pro 4 $0.1 vs $0.09

Solar Pro 4 is $0.01 cheaper on the standard workload (10.5% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.

Monthly input tokens Monthly output tokens

DeepSeek V4 Flash 0423 Calculating… Estimated API cost

Solar Pro 4 Calculating… Estimated API cost

Cheaper for this workload Calculating… Difference: calculating…

This estimate uses normalized public API pricing per 1M tokens. It is a planning aid, not a billing quote. Verify provider pricing, limits, and terms before production use.

Quick Decision

Verdict

Solar Pro 4 has the lower input price; DeepSeek V4 Flash 0423 has the lower output price; DeepSeek V4 Flash 0423 offers the larger context window. For the 1M input plus 500K output sample, Solar Pro 4 is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $0.1 for DeepSeek V4 Flash 0423 and $0.09 for Solar Pro 4.

Best Fit

Choose DeepSeek V4 Flash 0423 when you care most about lower output-token price, and larger context window.

Choose Solar Pro 4 when you care most about lower input-token price.

Decision Notes

On the standard 1M input plus 500K output workload, Solar Pro 4 is estimated at $0.09 vs $0.1 for DeepSeek V4 Flash 0423, saving $0.01 (10.5% lower).
Solar Pro 4 is $0.01 cheaper on the standard workload (10.5% lower).
Solar Pro 4 is $0.02 cheaper per 1M input tokens (40.4% lower; 1.68x difference).
DeepSeek V4 Flash 0423 is $0.02 cheaper per 1M output tokens (16.2% lower; 1.19x difference).
DeepSeek V4 Flash 0423 has 524.29K more context (2x larger).

Head-to-Head Specs

Feature	🔥DeepSeek V4 Flash 0423 (DeepSeek)	Solar Pro 4 (Upstage)
Input Price prompt tokens per 1M	$0.0503	$0.03
Completion Price per 1M tokens	$0.1005	$0.12
Sample Workload Cost 1M input + 500K output	$0.1	$0.09
Context Window	1.05M	524.29K
Release Date	2026-04-24	2026-08-10
Popularity	#5

Use-Case Decision Matrix

Use case	Better pick	Why
Budget-constrained production	Solar Pro 4	On the standard 1M input plus 500K output workload, Solar Pro 4 is estimated at $0.09 vs $0.1 for DeepSeek V4 Flash 0423, saving $0.01 (10.5% lower).
High-volume input processing	Solar Pro 4	Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbots	DeepSeek V4 Flash 0423	Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document work	DeepSeek V4 Flash 0423	A larger context window leaves more room for retrieved passages, conversation history, or source files.

Related Alternatives

Same-provider lower-cost swaps

DeepSeek V4 Flash (free) can replace DeepSeek V4 Flash 0423 when lower sample workload cost matters most: $0.

Larger context near this budget

DeepSeek V4 Flash Latest offers 1.31M context with $0.11 sample workload cost.
Owl Alpha offers 1.05M context with $0 sample workload cost.

Popular competitors

DeepSeek V4 Flash 0731 · DeepSeek · #1
MiMo-V2.5 · Xiaomi · #2
Hy3 · Tencent · #3
Ox Alpha · stealth · #4

Cheaper alternatives

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Larger context alternatives

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Provider catalogs

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DeepSeek catalog

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Upstage catalog

Check other Upstage models with comparable pricing, context, or release timing.

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DeepSeek V4 Flash 0423

DeepSeek V4 Flash is an efficiency-optimized Mixture-of-Experts model from DeepSeek with 284B total parameters and 13B activated parameters, supporting a 1M-token context window. It is designed for fast inference and...

Solar Pro 4

Solar Pro 4 is Upstage's cost-efficient large language model, featuring a 524K context window. It is built for long-horizon tasks and agentic workflows, with strong capabilities in office productivity, document-intensive...