Budget Mid

GPT-5 mini vs Gemini 3.5 Flash

Budget vs mid-tier AI models head-to-head. GPT-5 mini is 83% cheaper on input ($0.25 vs $1.50) and 78% cheaper on output ($2.00 vs $9.00). Gemini 3.5 Flash counters with a 1M context window — 3.7x larger than GPT-5 mini's 272K.

Pricing data verified: 2026-06-21

SpecificationGPT-5 mini (OpenAI)Gemini 3.5 Flash (Google)
Input Price (per 1M tokens)$0.25$1.50
Output Price (per 1M tokens)$2.00$9.00
Context Window272K1M
TierBudgetMid
ProviderOpenAIGoogle

Calculate Your Exact Costs

See how the costs stack up for your specific usage pattern.

OpenAI
GPT-5 mini
$0.00
per month
Input cost
Output cost
Cost per request
Requests/month
Google
Gemini 3.5 Flash
$0.00
per month
Input cost
Output cost
Cost per request
Requests/month

Other Models to Consider

DeepSeek V4 Pro
DeepSeek
$0.435 / $0.87 per 1M
1M context
Gemini 3 Flash
Google
$0.50 / $3.00 per 1M
1M context
Mistral Small 4
Mistral
$0.10 / $0.30 per 1M
128K context

Which Model for Which Use Case?

Cost-Sensitive Workloads

GPT-5 mini dominates on price: 83% cheaper on input ($0.25 vs $1.50/M) and 78% cheaper on output ($2.00 vs $9.00/M). For high-volume classification, search, or any budget-conscious workload, GPT-5 mini is the clear winner.

Much cheaper: GPT-5 mini

Long Context Tasks

Gemini 3.5 Flash's 1M token context window is 3.7x larger than GPT-5 mini's 272K. For processing long documents, entire codebases, or maintaining extended conversation history, Gemini handles far more context.

Better context: Gemini 3.5 Flash

High-Volume Production

At scale, GPT-5 mini's pricing advantage is massive. Running 10,000 requests/day with 1K input and 500 output tokens costs about $375/mo on GPT-5 mini vs $1,800/mo on Gemini 3.5 Flash — a 79% savings.

Better value at scale: GPT-5 mini

Multimodal & Google Cloud

Gemini 3.5 Flash offers Google's multimodal capabilities and tight integration with Google Cloud services. If you need image/video understanding or are invested in GCP, Gemini's ecosystem may justify the premium.

Better ecosystem: Gemini 3.5 Flash

Comparing Budget vs Mid Models?

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Frequently Asked Questions

Is GPT-5 mini cheaper than Gemini 3.5 Flash?

Yes, significantly. GPT-5 mini costs $0.25/M input (83% cheaper than Gemini 3.5 Flash's $1.50/M) and $2.00/M output (78% cheaper than Gemini 3.5 Flash's $9.00/M). For most workloads, GPT-5 mini costs a fraction of what Gemini 3.5 Flash costs.

When would I choose Gemini 3.5 Flash over GPT-5 mini?

Choose Gemini 3.5 Flash when you need a 1M token context window (3.7x larger than GPT-5 mini's 272K), Google's multimodal capabilities, or tight integration with Google Cloud. For long documents, large codebases, or extended conversations, Gemini's context window is the deciding factor.

Which model has a better context window?

Gemini 3.5 Flash has a 1M token context window — 3.7x larger than GPT-5 mini's 272K. If your workload requires processing very long documents or maintaining extended conversation history, Gemini 3.5 Flash is the clear winner on context.

How much can I save by choosing GPT-5 mini over Gemini 3.5 Flash?

For a typical workload of 1,000 input tokens and 500 output tokens at 1,000 requests per day, GPT-5 mini costs roughly $37.50/month vs Gemini 3.5 Flash's $180/month — saving you about $142/month or roughly 79%. The savings scale linearly with volume.

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