API cost decision in 10 seconds

GPT-5.3-Codex vs Solar Pro 3

Pick Solar Pro 3 for lower cost; pick GPT-5.3-Codex only if the larger context window matters more.

Pricing data updated: 2026-05-26T11:08:00Z Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick Solar Pro 3 for lower cost; pick GPT-5.3-Codex only if the larger context window matters more.

On the standard 1M input plus 500K output workload, Solar Pro 3 is estimated at $0.45 vs $8.75 for GPT-5.3-Codex, saving $8.3 (94.9% lower).

Cost-first pickSolar Pro 3

Context-first pickGPT-5.3-Codex

Sample savings$8.394.9%

10x traffic gap$83

GPT-5.3-Codex has more context, but Solar Pro 3 saves $8.3 on the standard workload. At 10x that traffic, the same price gap is about $83. 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 3 stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shape	Token mix	Better pick	GPT-5.3-Codex	Solar Pro 3
Input-heavy / RAG	5M input + 500K output	Solar Pro 3	$15.75	$1.05
Balanced workload	1M input + 1M output	Solar Pro 3	$15.75	$0.75
Output-heavy chatbot	1M input + 5M output	Solar Pro 3	$71.75	$3.15

Cheaper input Solar Pro 3 $1.75 vs $0.15 / 1M

Solar Pro 3 is $1.6 cheaper per 1M input tokens (91.4% lower; 11.7x difference).

Cheaper output Solar Pro 3 $14 vs $0.6 / 1M

Solar Pro 3 is $13.4 cheaper per 1M output tokens (95.7% lower; 23.3x difference).

Larger context GPT-5.3-Codex 400K vs 128K

GPT-5.3-Codex has 272K more context (3.12x larger).

Sample workload Solar Pro 3 $8.75 vs $0.45

Solar Pro 3 is $8.3 cheaper on the standard workload (94.9% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.

Monthly input tokens Monthly output tokens

GPT-5.3-Codex Calculating… Estimated API cost

Solar Pro 3 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 3 has the lower input price; Solar Pro 3 has the lower output price; GPT-5.3-Codex offers the larger context window. For the 1M input plus 500K output sample, Solar Pro 3 is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $8.75 for GPT-5.3-Codex and $0.45 for Solar Pro 3.

Best Fit

Choose GPT-5.3-Codex when you care most about larger context window.

Choose Solar Pro 3 when you care most about lower input-token price, and lower output-token price.

Decision Notes

On the standard 1M input plus 500K output workload, Solar Pro 3 is estimated at $0.45 vs $8.75 for GPT-5.3-Codex, saving $8.3 (94.9% lower).
Solar Pro 3 is $8.3 cheaper on the standard workload (94.9% lower).
Solar Pro 3 is $1.6 cheaper per 1M input tokens (91.4% lower; 11.7x difference).
Solar Pro 3 is $13.4 cheaper per 1M output tokens (95.7% lower; 23.3x difference).
GPT-5.3-Codex has 272K more context (3.12x larger).

Head-to-Head Specs

Feature	GPT-5.3-Codex (OpenAI)	Solar Pro 3 (Upstage)
Input Price prompt tokens per 1M	$1.75	$0.15
Completion Price per 1M tokens	$14	$0.6
Sample Workload Cost 1M input + 500K output	$8.75	$0.45
Context Window	400K	128K
Release Date	2026-02-24	2026-01-27

Use-Case Decision Matrix

Use case	Better pick	Why
Budget-constrained production	Solar Pro 3	On the standard 1M input plus 500K output workload, Solar Pro 3 is estimated at $0.45 vs $8.75 for GPT-5.3-Codex, saving $8.3 (94.9% lower).
High-volume input processing	Solar Pro 3	Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbots	Solar Pro 3	Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document work	GPT-5.3-Codex	A larger context window leaves more room for retrieved passages, conversation history, or source files.

Related Alternatives

Same-provider lower-cost swaps

gpt-oss-120b (free) can replace GPT-5.3-Codex when lower sample workload cost matters most: $0.
gpt-oss-20b (free) can replace GPT-5.3-Codex when lower sample workload cost matters most: $0.
gpt-oss-20b can replace GPT-5.3-Codex when lower sample workload cost matters most: $0.1.
gpt-oss-120b can replace GPT-5.3-Codex when lower sample workload cost matters most: $0.13.

Larger context near this budget

Llama 4 Scout offers 10M context with $0.23 sample workload cost.
Grok 4.20 Multi-Agent offers 2M context with $5 sample workload cost.
Grok 4.20 offers 2M context with $2.5 sample workload cost.
GPT-5.4 offers 1.05M context with $10 sample workload cost.

Popular competitors

No popular competitor is currently available.

Cheaper alternatives

Review low-cost models sorted by a standard 1M input plus 500K output workload.

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Larger context alternatives

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Provider catalogs

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OpenAI catalog

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Upstage catalog

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GPT-5.3-Codex

GPT-5.3-Codex is OpenAI’s most advanced agentic coding model, combining the frontier software engineering performance of GPT-5.2-Codex with the broader reasoning and professional knowledge capabilities of GPT-5.2. It achieves state-of-the-art results...

Solar Pro 3

Solar Pro 3 is Upstage's powerful Mixture-of-Experts (MoE) language model. With 102B total parameters and 12B active parameters per forward pass, it delivers exceptional performance while maintaining computational efficiency. Optimized...