API cost decision in 10 seconds

🔥GPT-5.5 vs 🔥Gemini 3.1 Flash Lite Preview

Pick Gemini 3.1 Flash Lite Preview for lower cost; pick GPT-5.5 only if the larger context window matters more.

Pricing data updated: 2026-05-17T02:07:32Z Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick Gemini 3.1 Flash Lite Preview for lower cost; pick GPT-5.5 only if the larger context window matters more.

On the standard 1M input plus 500K output workload, Gemini 3.1 Flash Lite Preview is estimated at $1 vs $20 for GPT-5.5, saving $19 (95% lower).

Cost-first pickGemini 3.1 Flash Lite Preview

Context-first pickGPT-5.5

Sample savings$1995%

10x traffic gap$190

GPT-5.5 has more context, but Gemini 3.1 Flash Lite Preview saves $19 on the standard workload. At 10x that traffic, the same price gap is about $190. Use the calculator below to replace the sample workload with your own token volume.

Cheaper input Gemini 3.1 Flash Lite Preview $5 vs $0.25 / 1M

Gemini 3.1 Flash Lite Preview is $4.75 cheaper per 1M input tokens (95% lower; 20x difference).

Cheaper output Gemini 3.1 Flash Lite Preview $30 vs $1.5 / 1M

Gemini 3.1 Flash Lite Preview is $28.5 cheaper per 1M output tokens (95% lower; 20x difference).

Larger context GPT-5.5 1.05M vs 1.05M

GPT-5.5 has 1.42K more context (1x larger).

Sample workload Gemini 3.1 Flash Lite Preview $20 vs $1

Gemini 3.1 Flash Lite Preview is $19 cheaper on the standard workload (95% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.

Monthly input tokens Monthly output tokens

GPT-5.5 Calculating… Estimated API cost

Gemini 3.1 Flash Lite Preview 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 Preview has the lower input price; Gemini 3.1 Flash Lite Preview has the lower output price; GPT-5.5 offers the larger context window. For the 1M input plus 500K output sample, Gemini 3.1 Flash Lite Preview is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $20 for GPT-5.5 and $1 for Gemini 3.1 Flash Lite Preview.

Best Fit

Choose GPT-5.5 when you care most about larger context window.

Choose Gemini 3.1 Flash Lite Preview 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 Preview is estimated at $1 vs $20 for GPT-5.5, saving $19 (95% lower).
Gemini 3.1 Flash Lite Preview is $19 cheaper on the standard workload (95% lower).
Gemini 3.1 Flash Lite Preview is $4.75 cheaper per 1M input tokens (95% lower; 20x difference).
Gemini 3.1 Flash Lite Preview is $28.5 cheaper per 1M output tokens (95% lower; 20x difference).
GPT-5.5 has 1.42K more context (1x larger).

Head-to-Head Specs

Feature	🔥GPT-5.5 (OpenAI)	🔥Gemini 3.1 Flash Lite Preview (Google)
Input Price prompt tokens per 1M	$5	$0.25
Completion Price per 1M tokens	$30	$1.5
Sample Workload Cost 1M input + 500K output	$20	$1
Context Window	1.05M	1.05M
Release Date	2026-04-24	2026-03-03
Popularity Rank current rank	#15	#19

Use-Case Decision Matrix

Use case	Better pick	Why
Budget-constrained production	Gemini 3.1 Flash Lite Preview	On the standard 1M input plus 500K output workload, Gemini 3.1 Flash Lite Preview is estimated at $1 vs $20 for GPT-5.5, saving $19 (95% lower).
High-volume input processing	Gemini 3.1 Flash Lite Preview	Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbots	Gemini 3.1 Flash Lite Preview	Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document work	GPT-5.5	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-5.5 when lower sample workload cost matters most: $0.
gpt-oss-20b (free) can replace GPT-5.5 when lower sample workload cost matters most: $0.
gpt-oss-20b can replace GPT-5.5 when lower sample workload cost matters most: $0.1.
gpt-oss-120b can replace GPT-5.5 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.

Popular competitors

DeepSeek V4 Flash · DeepSeek · #1
Hy3 preview · Tencent · #2
Claude Sonnet 4.6 · Anthropic · #3
Owl Alpha · OpenRouter · #4

Cheaper alternatives

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Larger context alternatives

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OpenAI catalog

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Google catalog

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GPT-5.5

GPT-5.5 is OpenAI’s frontier model designed for complex professional workloads, building on GPT-5.4 with stronger reasoning, higher reliability, and improved token efficiency on hard tasks. It features a 1M+ token...

Gemini 3.1 Flash Lite Preview

Gemini 3.1 Flash Lite Preview is Google's high-efficiency model optimized for high-volume use cases. It outperforms Gemini 2.5 Flash Lite on overall quality and approaches Gemini 2.5 Flash performance across...