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ModelCap

Head-to-head comparison

Gemini 3.8 Flash vs GLM 5.3

Gemini 3.8 Flash (Google) and GLM 5.3 (Z.ai) compared on the ModelCap Index, API price, context window, provider availability, weight access and every public benchmark board they share. Figures are the same ones shown on the live rankings; nothing here is a hidden score.

Snapshot as of 9 September 2026

As of 9 September 2026, Gemini 3.8 Flash holds the stronger ModelCap Index position (#7 vs #8); and Gemini 3.8 Flash is 1.2× cheaper per output token ($3.75/1M vs $4.40/1M).

Which should you choose?

Choose Gemini 3.8 Flash if…

  • you want the stronger overall ModelCap Index position — #7 against #8 (82.2 vs 82.1 points).
  • API cost matters — $3.75/1M output tokens against $4.40/1M, about 1.2× cheaper.
  • your workload is prompt-heavy — input tokens cost $0.75/1M against $1.40/1M.
  • Arena coding is your yardstick — 1537 against 1528.
  • LMArena Agent is your yardstick — 4.0% against 2.6%.
  • AA Terminal-Bench 2.1 is your yardstick — 87.6% against 83.9%.
  • AA Humanity's Last Exam is your yardstick — 47.8% against 42.3%.
  • you want the more recently listed model — Gemini 3.8 Flash was listed 2 September 2026, GLM 5.3 18 August 2026.

Choose GLM 5.3 if…

  • you want provider choice — 26 listed API providers against 2.
  • AA Intelligence Index is your yardstick — 44.9 against 41.2.
  • Terminal-Bench 4.0 is your yardstick — 41.8% against 19.1%.

Gemini 3.8 Flash vs GLM 5.3: specs, pricing and context

Specification comparison of Gemini 3.8 Flash and GLM 5.3
FieldGemini 3.8 FlashGoogleGLM 5.3Z.ai
ModelCap Index position#7#8
Index score82.282.1
EvidenceMeasuredMeasured
Input price / 1M tokens$0.75$1.40
Output price / 1M tokens$3.75$4.40
Context window1M tokens1M tokens
Max output tokens66K944K
API providers listed226
Weight accessAPI onlyRestricted license
Input modalitiesText, Image, Video, File, AudioText
First listed2 September 202618 August 2026
PublisherGoogleZ.ai

Evidence: 4 public benchmark observations across 4 boards · 4 public benchmark observations across 4 boards. Prices are the lowest listed API offer per million tokens observed on the OpenRouter catalogue.

Benchmark scores: Gemini 3.8 Flash vs GLM 5.3

Public benchmark boards where Gemini 3.8 Flash or GLM 5.3 has a published result
BoardGemini 3.8 FlashGLM 5.3Leads
Arena codingArena (LMArena)15371521–1553High15281514–1541MaxGemini 3.8 Flash
LMArena AgentLMArena4.0%2.1%–6.0%High2.6%1.9%–3.2%MaxGemini 3.8 Flash
AA Intelligence IndexArtificial Analysis41.2intelligence-index:v4.3:high44.9intelligence-index:v4.3:maxGLM 5.3
AA Terminal-Bench 2.1Artificial Analysis87.6%terminal-bench:2.1:terminus-2:e2b:pass-at-1:3-repeats:source-model="Gemini 3.8 Flash (high)":reasoning=true83.9%terminal-bench:2.1:terminus-2:e2b:pass-at-1:3-repeats:source-model="GLM-5.3 (max)":reasoning=trueGemini 3.8 Flash
AA Humanity's Last ExamArtificial Analysis47.8%hle:may-2025:text-only-2158:no-tools:pass-at-1:source-model="Gemini 3.8 Flash (high)":reasoning=true42.3%hle:may-2025:text-only-2158:no-tools:pass-at-1:source-model="GLM-5.3 (max)":reasoning=trueGemini 3.8 Flash
Terminal-Bench 4.0Terminal-Bench (Laude Institute)19.1%15.7%–22.5%mini-SWE-agent · High41.8%38.6%–45.1%Claude Code · MaxGLM 5.3

Scores are the sources' own published figures for each model's best evaluated configuration; ModelCap never re-runs a benchmark.

Want a different pairing? Open the interactive comparison tool to swap either model for any current ranked language model.

Gemini 3.8 Flash vs GLM 5.3: common questions

Is Gemini 3.8 Flash better than GLM 5.3?

Gemini 3.8 Flash ranks higher on the ModelCap Index as of 9 September 2026: #7 against #8. That is a capability ranking built from public benchmark evidence with published uncertainty; whether it is "better" for you also depends on price, context and where you can run it. Their published uncertainty intervals overlap, so the rank difference alone does not establish a reliable capability advantage for your workload.

Is Gemini 3.8 Flash cheaper than GLM 5.3?

Gemini 3.8 Flash is cheaper on output tokens: $3.75/1M against $4.40/1M. Input tokens are $0.75/1M for Gemini 3.8 Flash and $1.40/1M for GLM 5.3. Prices are the lowest listed API offer ModelCap observed, in USD per million tokens. For 1,000 requests with 2,000 input and 500 output tokens each (2M input + 0.5M output), the listed-rate estimate is $3.38 for Gemini 3.8 Flash versus $5.00 for GLM 5.3. Gemini 3.8 Flash costs 32.5% less in this scenario. This excludes caching, batch discounts, prompt-length tiers, tool charges and retries; verify the selected endpoint before budgeting.

Which has the bigger context window, Gemini 3.8 Flash or GLM 5.3?

Both publish a 1M-token context window.

Which is better for coding, Gemini 3.8 Flash or GLM 5.3?

Arena coding: Gemini 3.8 Flash 1537, GLM 5.3 1528 — Gemini 3.8 Flash leads. AA Terminal-Bench 2.1: Gemini 3.8 Flash 87.6%, GLM 5.3 83.9% — Gemini 3.8 Flash leads. Terminal-Bench 4.0: Gemini 3.8 Flash 19.1%, GLM 5.3 41.8% — GLM 5.3 leads.

Are Gemini 3.8 Flash and GLM 5.3 open-weight models?

Gemini 3.8 Flash: API only. GLM 5.3: Restricted license. Open weights mean the checkpoint can be downloaded and self-hosted under its licence; API-only models are available solely through hosted endpoints.

Where can I run Gemini 3.8 Flash and GLM 5.3?

ModelCap currently lists 2 API providers for Gemini 3.8 Flash and 26 for GLM 5.3, from the OpenRouter catalogue snapshot the site serves; each model page lists the providers and their prices.

How current is this Gemini 3.8 Flash vs GLM 5.3 comparison?

Every figure comes from the sealed ModelCap dataset published 9 September 2026; the page re-renders within a minute of each data refresh, and the ModelCap Index positions are the same ones shown on the live rankings.

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