API cost decision in 10 seconds

🔥Gemini 3 Flash Preview vs 🔥GLM 5.1

Pick Gemini 3 Flash Preview when budget and context both matter.

Pricing data updated: 2026-05-15T02:08:14Z Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick Gemini 3 Flash Preview when budget and context both matter.

On the standard 1M input plus 500K output workload, Gemini 3 Flash Preview is estimated at $2 vs $2.52 for GLM 5.1, saving $0.52 (20.6% lower).

Cost-first pickGemini 3 Flash Preview

Context-first pickGemini 3 Flash Preview

Sample savings$0.5220.6%

10x traffic gap$5.2

Gemini 3 Flash Preview is cheaper on the standard workload and also has the larger context window. At 10x that traffic, the same price gap is about $5.2. Use the calculator below to replace the sample workload with your own token volume.

Cheaper input Gemini 3 Flash Preview $0.5 vs $0.98 / 1M

Gemini 3 Flash Preview is $0.48 cheaper per 1M input tokens (49% lower; 1.96x difference).

Cheaper output Gemini 3 Flash Preview $3 vs $3.08 / 1M

Gemini 3 Flash Preview is $0.08 cheaper per 1M output tokens (2.6% lower; 1.03x difference).

Larger context Gemini 3 Flash Preview 1.05M vs 202.75K

Gemini 3 Flash Preview has 845.82K more context (5.17x larger).

Sample workload Gemini 3 Flash Preview $2 vs $2.52

Gemini 3 Flash Preview is $0.52 cheaper on the standard workload (20.6% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.

Monthly input tokens Monthly output tokens

Gemini 3 Flash Preview Calculating… Estimated API cost

GLM 5.1 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 Flash Preview has the lower input price; Gemini 3 Flash Preview has the lower output price; Gemini 3 Flash Preview offers the larger context window. For the 1M input plus 500K output sample, Gemini 3 Flash Preview is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $2 for Gemini 3 Flash Preview and $2.52 for GLM 5.1.

Best Fit

Choose Gemini 3 Flash Preview when you care most about lower input-token price, lower output-token price, and larger context window.

Choose GLM 5.1 when its provider, model quality, latency, or availability is more important than the numeric price/context winner.

Decision Notes

On the standard 1M input plus 500K output workload, Gemini 3 Flash Preview is estimated at $2 vs $2.52 for GLM 5.1, saving $0.52 (20.6% lower).
Gemini 3 Flash Preview is $0.52 cheaper on the standard workload (20.6% lower).
Gemini 3 Flash Preview is $0.48 cheaper per 1M input tokens (49% lower; 1.96x difference).
Gemini 3 Flash Preview is $0.08 cheaper per 1M output tokens (2.6% lower; 1.03x difference).
Gemini 3 Flash Preview has 845.82K more context (5.17x larger).

Head-to-Head Specs

Feature	🔥Gemini 3 Flash Preview (Google)	🔥GLM 5.1 (Z.ai)
Input Price prompt tokens per 1M	$0.5	$0.98
Completion Price per 1M tokens	$3	$3.08
Sample Workload Cost 1M input + 500K output	$2	$2.52
Context Window	1.05M	202.75K
Release Date	2025-12-17	2026-04-07
Popularity Rank current rank	#5	#20

Use-Case Decision Matrix

Use case	Better pick	Why
Budget-constrained production	Gemini 3 Flash Preview	On the standard 1M input plus 500K output workload, Gemini 3 Flash Preview is estimated at $2 vs $2.52 for GLM 5.1, saving $0.52 (20.6% lower).
High-volume input processing	Gemini 3 Flash Preview	Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbots	Gemini 3 Flash Preview	Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document work	Gemini 3 Flash Preview	A larger context window leaves more room for retrieved passages, conversation history, or source files.

Related Alternatives

Same-provider lower-cost swaps

Gemma 4 26B A4B (free) can replace Gemini 3 Flash Preview when lower sample workload cost matters most: $0.
Gemma 4 31B (free) can replace Gemini 3 Flash Preview when lower sample workload cost matters most: $0.
Lyria 3 Pro Preview can replace Gemini 3 Flash Preview when lower sample workload cost matters most: $0.
Lyria 3 Clip Preview can replace Gemini 3 Flash Preview when lower sample workload cost matters most: $0.

Larger context near this budget

Grok 4.1 Fast offers 2M context with $0.45 sample workload cost.
Grok 4.20 offers 2M context with $2.5 sample workload cost.
Grok 4 Fast offers 2M context with $0.45 sample workload cost.
Owl Alpha offers 1.05M context with $0 sample workload cost.

Popular competitors

Hy3 preview · Tencent · #1
Claude Opus 4.7 · Anthropic · #2
Claude Sonnet 4.6 · Anthropic · #3
DeepSeek V4 Flash · DeepSeek · #4

Cheaper alternatives

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Larger context alternatives

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Provider catalogs

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Google catalog

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Z.ai catalog

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