API cost decision in 10 seconds

GPT-5.6 Sol Pro (batch) vs Gemini 3.1 Flash Lite (batch)

Pick Gemini 3.1 Flash Lite (batch) for lower cost; pick GPT-5.6 Sol Pro (batch) only if the larger context window matters more.

Page updated:  Data confirmed:  Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick Gemini 3.1 Flash Lite (batch) for lower cost; pick GPT-5.6 Sol Pro (batch) only if the larger context window matters more.

On the standard 1M input plus 500K output workload, Gemini 3.1 Flash Lite (batch) is estimated at $0.5 vs $3.5 for GPT-5.6 Sol Pro (batch), saving $3 (85.7% lower).

Cost-first pickGemini 3.1 Flash Lite (batch)
Context-first pickGPT-5.6 Sol Pro (batch)
Sample savings$385.7%
10x traffic gap$30

GPT-5.6 Sol Pro (batch) has more context, but Gemini 3.1 Flash Lite (batch) saves $3 on the standard workload. At 10x that traffic, the same price gap is about $30. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

Gemini 3.1 Flash Lite (batch) stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shapeToken mixBetter pickGPT-5.6 Sol Pro (batch)Gemini 3.1 Flash Lite (batch)
Input-heavy / RAG5M input + 500K outputGemini 3.1 Flash Lite (batch)$7.5$1
Balanced workload1M input + 1M outputGemini 3.1 Flash Lite (batch)$6$0.88
Output-heavy chatbot1M input + 5M outputGemini 3.1 Flash Lite (batch)$26$3.88
Cheaper input Gemini 3.1 Flash Lite (batch) $1 vs $0.125 / 1M

Gemini 3.1 Flash Lite (batch) is $0.88 cheaper per 1M input tokens (87.5% lower; 8x difference).

Cheaper output Gemini 3.1 Flash Lite (batch) $5 vs $0.75 / 1M

Gemini 3.1 Flash Lite (batch) is $4.25 cheaper per 1M output tokens (85% lower; 6.67x difference).

Larger context GPT-5.6 Sol Pro (batch) 1.05M vs 1.05M

GPT-5.6 Sol Pro (batch) has 1.42K more context (1x larger).

Sample workload Gemini 3.1 Flash Lite (batch) $3.5 vs $0.5

Gemini 3.1 Flash Lite (batch) is $3 cheaper on the standard workload (85.7% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.
GPT-5.6 Sol Pro (batch) Calculating… Estimated API cost
Gemini 3.1 Flash Lite (batch) 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

Gemini 3.1 Flash Lite (batch) has the lower input price; Gemini 3.1 Flash Lite (batch) has the lower output price; GPT-5.6 Sol Pro (batch) offers the larger context window. For the 1M input plus 500K output sample, Gemini 3.1 Flash Lite (batch) is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $3.5 for GPT-5.6 Sol Pro (batch) and $0.5 for Gemini 3.1 Flash Lite (batch).

Best Fit

Choose GPT-5.6 Sol Pro (batch) when you care most about larger context window.

Choose Gemini 3.1 Flash Lite (batch) 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, Gemini 3.1 Flash Lite (batch) is estimated at $0.5 vs $3.5 for GPT-5.6 Sol Pro (batch), saving $3 (85.7% lower).
  • Gemini 3.1 Flash Lite (batch) is $3 cheaper on the standard workload (85.7% lower).
  • Gemini 3.1 Flash Lite (batch) is $0.88 cheaper per 1M input tokens (87.5% lower; 8x difference).
  • Gemini 3.1 Flash Lite (batch) is $4.25 cheaper per 1M output tokens (85% lower; 6.67x difference).
  • GPT-5.6 Sol Pro (batch) has 1.42K more context (1x larger).
Head-to-Head Specs
FeatureGPT-5.6 Sol Pro (batch)
(OpenAI)		Gemini 3.1 Flash Lite (batch)
(Google)
Input Price
prompt tokens per 1M		$1$0.125
Completion Price
per 1M tokens		$5$0.75
Sample Workload Cost
1M input + 500K output		$3.5$0.5
Context Window1.05M1.05M
Release Date

Use-Case Decision Matrix

Use caseBetter pickWhy
Budget-constrained productionGemini 3.1 Flash Lite (batch)On the standard 1M input plus 500K output workload, Gemini 3.1 Flash Lite (batch) is estimated at $0.5 vs $3.5 for GPT-5.6 Sol Pro (batch), saving $3 (85.7% lower).
High-volume input processingGemini 3.1 Flash Lite (batch)Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbotsGemini 3.1 Flash Lite (batch)Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document workGPT-5.6 Sol Pro (batch)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-5.6 Sol Pro (batch) when lower sample workload cost matters most: $0.
  • gpt-oss-20b (free) can replace GPT-5.6 Sol Pro (batch) when lower sample workload cost matters most: $0.
  • gpt-oss-20b can replace GPT-5.6 Sol Pro (batch) when lower sample workload cost matters most: $0.1.
  • gpt-oss-120b can replace GPT-5.6 Sol Pro (batch) when lower sample workload cost matters most: $0.12.

Cheaper alternatives

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

Open cheapest models

Larger context alternatives

Find models with larger context windows for RAG, long documents, and codebase review.

Open largest context models

Provider catalogs

Compare models within provider hubs before choosing a final API vendor.

Open provider hubs

OpenAI catalog

Review all tracked OpenAI models before deciding whether this matchup is the right shortlist.

Open OpenAI models

Google catalog

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

Open Google models
GPT-5.6 Sol Pro (batch)

GPT-5.6 Sol Pro is the same underlying model as [GPT-5.6 Sol](https://openrouter.ai/openai/gpt-5.6-sol), served with `reasoning.mode` set to `pro` for higher-quality responses on complex tasks. Learn more in OpenAI's docs: https://developers.openai.com/api/docs/guides/reasoning#reasoning-mode

Gemini 3.1 Flash Lite (batch)

Gemini 3.1 Flash Lite is Google’s GA high-efficiency multimodal model optimized for low-latency, high-volume workloads. It supports text, image, video, audio, and PDF inputs, and is designed for lightweight agentic...