Google: Gemini 3.8 Flash vs Meta: Muse Spark Open

Neither wins outright: Google: Gemini 3.8 Flash is the pick when cost matters at scale, Meta: Muse Spark Open when you need log-probabilities.

Key numbers

SpecGoogle: Gemini 3.8 FlashMeta: Muse Spark Open
ProviderGoogleMeta
Input price (per 1M tokens)$0.82$1.25
Output price (per 1M tokens)$4.13$4.25
Blended price (3:1 input/output)$1.65$2.00
Cheaper than … of all models we track30%25%
Context window1.0M tokens (~1,573 pages)1.0M tokens (~1,573 pages)
Larger context than … of all models81%81%
Max output per response66K tokens (~49,200 words)944K tokens (~707,800 words)
Input typestext, image, video, file, audiotext, image, video, file, audio
Output typestexttext
Free variantNoNo
Listed since2026-09-022026-10-15

What it costs for real workloads

Monthly cost at list price for five common workloads. Token counts per unit are stated so you can scale them to your own traffic. A workload that does not fit a model's context window is marked rather than priced.

Workload (per month)Google: Gemini 3.8 FlashMeta: Muse Spark OpenDifference
Customer-support chatbot
50,000 conversations — each a 6-turn conversation (1,500 in / 400 out tokens)
$144$179Google: Gemini 3.8 Flash saves $34.38
RAG search over documents
20,000 questions — each a question answered from ~8 retrieved passages (6,000 in / 500 out tokens)
$140$193Google: Gemini 3.8 Flash saves $52.25
Coding / tool-using agent
2,000 tasks — each a multi-step task with tool calls and file context (60,000 in / 6,000 out tokens)
$149$201Google: Gemini 3.8 Flash saves $52.50
Batch summarisation
10,000 documents — each a 6,000-word report summarised to a page (8,000 in / 600 out tokens)
$90.75$126Google: Gemini 3.8 Flash saves $34.75
Long-document analysis
500 documents — each a 150-page contract or codebase read in one pass (100,000 in / 2,000 out tokens)
$45.38$66.75Google: Gemini 3.8 Flash saves $21.38

Capabilities side by side

CapabilityGoogle: Gemini 3.8 FlashMeta: Muse Spark OpenWhat it lets you do
Tool / function calling✓ Yes✓ Yescall your APIs and run agent loops
Structured output (JSON schema)✓ Yes✓ Yesreturn JSON that validates against your schema
Reasoning / thinking mode✓ Yes✓ Yesspend extra tokens thinking before answering hard problems
Image input✓ Yes✓ Yesread screenshots, charts and scanned pages
Audio input✓ Yes✓ Yestake speech or audio directly
File / PDF input✓ Yes✓ Yesaccept documents without your own parsing step
Image output——generate images, not just text
Built-in web search✓ Yes—answer from live web results
Seed (reproducible sampling)✓ Yes✓ Yesrepeat a generation for tests and evals
Log-probabilities—✓ Yesread token confidence for classification and scoring

From each model's published parameters and input/output types. “—” means not advertised, not proven absent.

Price history

DateModelInput / 1MOutput / 1M
2026-10-16Google: Gemini 3.8 Flash$0.82$4.13

Which should you choose?

Choose Google: Gemini 3.8 Flash if…

  • cost matters at scale — it is 18% cheaper on a typical 3:1 input/output mix ($144 vs $179 a month for 50,000 support chats)
  • you need built-in web search — to answer from live web results; Meta: Muse Spark Open does not advertise it

Choose Meta: Muse Spark Open if…

  • you need log-probabilities — to read token confidence for classification and scoring; Google: Gemini 3.8 Flash does not advertise it
  • you generate long outputs in one go — up to 944K tokens (about 707,800 words) per response

Frequently asked questions

Is Google: Gemini 3.8 Flash better than Meta: Muse Spark Open?

Neither wins outright: Google: Gemini 3.8 Flash is the pick when cost matters at scale, Meta: Muse Spark Open when you need log-probabilities. In short: Google: Gemini 3.8 Flash when cost matters at scale, you need built-in web search; Meta: Muse Spark Open when you need log-probabilities, you generate long outputs in one go.

Which is cheaper, Google: Gemini 3.8 Flash or Meta: Muse Spark Open?

Google: Gemini 3.8 Flash is cheaper: $1.65 vs $2.00 per 1M tokens at a typical 3:1 input/output mix, 18% less. For 50,000 support conversations a month that is $144 against $179.

How much do Google: Gemini 3.8 Flash and Meta: Muse Spark Open cost per million tokens?

Google: Gemini 3.8 Flash costs $0.82 per 1M input tokens and $4.13 per 1M output tokens; Meta: Muse Spark Open costs $1.25 input and $4.25 output. Output tokens are billed separately, so long answers shift the gap.

Which has the bigger context window, Google: Gemini 3.8 Flash or Meta: Muse Spark Open?

Both take 1.0M tokens per request — roughly 1,573 pages of text.

Do Google: Gemini 3.8 Flash and Meta: Muse Spark Open support function calling and JSON output?

Tool calling — Google: Gemini 3.8 Flash: yes, Meta: Muse Spark Open: yes. JSON-schema structured output — Google: Gemini 3.8 Flash: yes, Meta: Muse Spark Open: yes.

Can Google: Gemini 3.8 Flash or Meta: Muse Spark Open read images?

Yes, both accept image input.

Is Google: Gemini 3.8 Flash or Meta: Muse Spark Open free to use?

No free variant is listed for either; both are pay-per-token.

What is the maximum output length of Google: Gemini 3.8 Flash and Meta: Muse Spark Open?

Google: Gemini 3.8 Flash can write up to 66K tokens (about 49,200 words) per response; Meta: Muse Spark Open up to 944K (about 707,800 words).

When were Google: Gemini 3.8 Flash and Meta: Muse Spark Open released?

Google: Gemini 3.8 Flash was listed on 2026-09-02; Meta: Muse Spark Open on 2026-10-15.

Has the price of Google: Gemini 3.8 Flash or Meta: Muse Spark Open changed?

Google: Gemini 3.8 Flash: input price raised 9% ($0.75 → $0.82/1M), output price raised 9% ($3.75 → $4.13/1M) on 2026-10-16. Meta: Muse Spark Open: price unchanged since we started tracking it on 2026-10-16.

About the two models

Meta

Meta: Muse Spark Open

Muse Spark Open is a coding-optimized open-weight model. Trained specifically for agentic coding workflows, it delivers higher first-attempt accuracy, reliable tool calling, and deep codebase understanding across the repos developers...

Full Meta: Muse Spark Open specs →

Compare Google: Gemini 3.8 Flash with other models

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