API cost decision in 10 seconds

Solar Pro 4 vs DeepSeek V4 Flash Latest

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

Page updated: 2026-08-23T07:07:52Z 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 Latest 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 $0.11 for DeepSeek V4 Flash Latest, saving $0.02 (14.3% lower).

Cost-first pickSolar Pro 4

Context-first pickDeepSeek V4 Flash Latest

Sample savings$0.0214.3%

10x traffic gap$0.15

DeepSeek V4 Flash Latest has more context, but Solar Pro 4 saves $0.02 on the standard workload. At 10x that traffic, the same price gap is about $0.15. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

Solar Pro 4 stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shape	Token mix	Better pick	Solar Pro 4	DeepSeek V4 Flash Latest
Input-heavy / RAG	5M input + 500K output	Solar Pro 4	$0.21	$0.27
Balanced workload	1M input + 1M output	Solar Pro 4	$0.15	$0.17
Output-heavy chatbot	1M input + 5M output	Solar Pro 4	$0.63	$0.69

Cheaper input Solar Pro 4 $0.03 vs $0.04 / 1M

Solar Pro 4 is $0.01 cheaper per 1M input tokens (25% lower; 1.33x difference).

Cheaper output Solar Pro 4 $0.12 vs $0.13 / 1M

Solar Pro 4 is $0.01 cheaper per 1M output tokens (7.7% lower; 1.08x difference).

Larger context DeepSeek V4 Flash Latest 524.29K vs 1.31M

DeepSeek V4 Flash Latest has 786.43K more context (2.5x larger).

Sample workload Solar Pro 4 $0.09 vs $0.11

Solar Pro 4 is $0.02 cheaper on the standard workload (14.3% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.

Monthly input tokens Monthly output tokens

Solar Pro 4 Calculating… Estimated API cost

DeepSeek V4 Flash Latest 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; Solar Pro 4 has the lower output price; DeepSeek V4 Flash Latest 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 $0.09 for Solar Pro 4 and $0.11 for DeepSeek V4 Flash Latest.

Best Fit

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

Choose DeepSeek V4 Flash Latest when you care most about larger context window.

Decision Notes

On the standard 1M input plus 500K output workload, Solar Pro 4 is estimated at $0.09 vs $0.11 for DeepSeek V4 Flash Latest, saving $0.02 (14.3% lower).
Solar Pro 4 is $0.02 cheaper on the standard workload (14.3% lower).
Solar Pro 4 is $0.01 cheaper per 1M input tokens (25% lower; 1.33x difference).
Solar Pro 4 is $0.01 cheaper per 1M output tokens (7.7% lower; 1.08x difference).
DeepSeek V4 Flash Latest has 786.43K more context (2.5x larger).

Head-to-Head Specs

Feature	Solar Pro 4 (Upstage)	DeepSeek V4 Flash Latest (deepseek)
Input Price prompt tokens per 1M	$0.03	$0.04
Completion Price per 1M tokens	$0.12	$0.13
Sample Workload Cost 1M input + 500K output	$0.09	$0.11
Context Window	524.29K	1.31M
Release Date	2026-08-10	2026-08-01

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 $0.11 for DeepSeek V4 Flash Latest, saving $0.02 (14.3% 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	Solar Pro 4	Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document work	DeepSeek V4 Flash Latest	A larger context window leaves more room for retrieved passages, conversation history, or source files.

Related Alternatives

Same-provider lower-cost swaps

No lower-cost same-provider swap is currently tracked for this pair.

Larger context near this budget

No larger-context model is currently tracked within a close sample-cost band.

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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Upstage catalog

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deepseek catalog

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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...

DeepSeek V4 Flash Latest

This model always redirects to the latest model in the DeepSeek V4 Flash family.