API cost decision in 10 seconds

New🔥Gemini 3.5 Flash vs GLM 5

Pick GLM 5 for lower cost; pick Gemini 3.5 Flash only if the larger context window matters more.

Page updated: 2026-05-26T12:03:47Z Data confirmed: 2026-05-26T13:08:02Z Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick GLM 5 for lower cost; pick Gemini 3.5 Flash only if the larger context window matters more.

On the standard 1M input plus 500K output workload, GLM 5 is estimated at $1.56 vs $6 for Gemini 3.5 Flash, saving $4.44 (74% lower).

Cost-first pickGLM 5

Context-first pickGemini 3.5 Flash

Sample savings$4.4474%

10x traffic gap$44.4

Gemini 3.5 Flash has more context, but GLM 5 saves $4.44 on the standard workload. At 10x that traffic, the same price gap is about $44.4. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

GLM 5 stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shape	Token mix	Better pick	Gemini 3.5 Flash	GLM 5
Input-heavy / RAG	5M input + 500K output	GLM 5	$12	$3.96
Balanced workload	1M input + 1M output	GLM 5	$10.5	$2.52
Output-heavy chatbot	1M input + 5M output	GLM 5	$46.5	$10.2

Cheaper input GLM 5 $1.5 vs $0.6 / 1M

GLM 5 is $0.9 cheaper per 1M input tokens (60% lower; 2.5x difference).

Cheaper output GLM 5 $9 vs $1.92 / 1M

GLM 5 is $7.08 cheaper per 1M output tokens (78.7% lower; 4.69x difference).

Larger context Gemini 3.5 Flash 1.05M vs 202.75K

Gemini 3.5 Flash has 845.82K more context (5.17x larger).

Sample workload GLM 5 $6 vs $1.56

GLM 5 is $4.44 cheaper on the standard workload (74% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.

Monthly input tokens Monthly output tokens

Gemini 3.5 Flash Calculating… Estimated API cost

GLM 5 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

GLM 5 has the lower input price; GLM 5 has the lower output price; Gemini 3.5 Flash offers the larger context window. For the 1M input plus 500K output sample, GLM 5 is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $6 for Gemini 3.5 Flash and $1.56 for GLM 5.

Best Fit

Choose Gemini 3.5 Flash when you care most about larger context window.

Choose GLM 5 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, GLM 5 is estimated at $1.56 vs $6 for Gemini 3.5 Flash, saving $4.44 (74% lower).
GLM 5 is $4.44 cheaper on the standard workload (74% lower).
GLM 5 is $0.9 cheaper per 1M input tokens (60% lower; 2.5x difference).
GLM 5 is $7.08 cheaper per 1M output tokens (78.7% lower; 4.69x difference).
Gemini 3.5 Flash has 845.82K more context (5.17x larger).

Head-to-Head Specs

Feature	New🔥Gemini 3.5 Flash (Google)	GLM 5 (Z.ai)
Input Price prompt tokens per 1M	$1.5	$0.6
Completion Price per 1M tokens	$9	$1.92
Sample Workload Cost 1M input + 500K output	$6	$1.56
Context Window	1.05M	202.75K
Release Date	2026-05-19	2026-02-11
Popularity	#11

Use-Case Decision Matrix

Use case	Better pick	Why
Budget-constrained production	GLM 5	On the standard 1M input plus 500K output workload, GLM 5 is estimated at $1.56 vs $6 for Gemini 3.5 Flash, saving $4.44 (74% lower).
High-volume input processing	GLM 5	Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbots	GLM 5	Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document work	Gemini 3.5 Flash	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 3.5 Flash when lower sample workload cost matters most: $0.
Gemma 4 31B (free) can replace Gemini 3.5 Flash when lower sample workload cost matters most: $0.
Lyria 3 Pro Preview can replace Gemini 3.5 Flash when lower sample workload cost matters most: $0.
Lyria 3 Clip Preview can replace Gemini 3.5 Flash when lower sample workload cost matters most: $0.

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.
Owl Alpha offers 1.05M context with $0 sample workload cost.

Popular competitors

DeepSeek V4 Flash · DeepSeek · #1
Hy3 preview · Tencent · #2
Claude Opus 4.7 · Anthropic · #3
Claude Sonnet 4.6 · Anthropic · #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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Gemini 3.5 Flash

Gemini 3.5 Flash is Google's high-efficiency multimodal model, bringing near-Pro level coding and reasoning at Flash-tier cost and speed. It is highly optimized for coding proficiency and parallel agentic execution...

GLM 5

GLM-5 is Z.ai’s flagship open-source foundation model engineered for complex systems design and long-horizon agent workflows. Built for expert developers, it delivers production-grade performance on large-scale programming tasks, rivaling leading...