Gemini 4 Carbon vs GLM 5.2

Google · US  |  Z.ai · China · Updated June 2026

Quick verdict

Pick Gemini 4 Carbon for ranked first on the artificial analysis intelligence index v5.0 with 59 at launch (artificial analysis now shows 60) or google-reported 88.2% on sec-bench pro and 54.8% on exploitgym for vulnerability discovery and exploit validation. Pick GLM 5.2 for long-horizon agentic coding or project-level software engineering. Choose GLM 5.2 if you need self-hosting or data privacy; Gemini 4 Carbon if you want a managed API.

Gemini 4 Carbon (Google, US) and GLM 5.2 (Z.ai, China) line up two different AI ecosystems against each other — a comparison that is as much about cost philosophy and openness as raw capability. Gemini 4 Carbon is google's October 28, 2026 limited release for cyber defenders - top of the Artificial Analysis index at launch, priced at $2/$10 introductory, with no public API date yet. GLM 5.2 is an open-weight reasoning model built for long-horizon coding and multi-step agent workflows — strong and cheap. They diverge most on price and open vs. closed weights — each quantified below from the models' real specs.

Key differences at a glance

Side-by-side specs

SpecGemini 4 CarbonGLM 5.2
ProviderGoogle (US) Z.ai (China)
ReleasedOctober 28, 2026 June 16, 2026
Context window1M tokens (~1,500 pages) 1M (~1,500 pages)
Price (in/out)$2/$10 per 1M tokens $1.4/$4.4 per 1M tokens
Open weight?No — API only Yes — self-hostable
Modalitiestext, image, audio, video, code text, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

Ranked first on the Artificial Analysis Intelligence Index v5.0 with 59 at launch (Artificial Analysis now shows 60)

Gemini 4 Carbon

Google's October 28, 2026 limited release for cyber defenders - top of the Artificial Analysis index at launch, priced at $2/$10 introductory, with no public API date yet — and it is the newer of the two.

Google-reported 88.2% on SEC-bench Pro and 54.8% on ExploitGym for vulnerability discovery and exploit validation

Gemini 4 Carbon

Gemini 4 Carbon lists google-reported 88.2% on SEC-bench Pro and 54.8% on ExploitGym for vulnerability discovery and exploit validation among its strengths; GLM 5.2 does not.

Google-reported 71.0% on CWE-bench for patching

Gemini 4 Carbon

Gemini 4 Carbon lists google-reported 71.0% on CWE-bench for patching among its strengths; GLM 5.2 does not.

Long-horizon agentic coding

GLM 5.2

An open-weight reasoning model built for long-horizon coding and multi-step agent workflows — strong and cheap — and it runs cheaper at $1.4/$4.4 per 1M tokens.

Project-level software engineering

GLM 5.2

An open-weight reasoning model built for long-horizon coding and multi-step agent workflows — strong and cheap — and its weights are open while Gemini 4 Carbon is API-only.

Tool use across long-running tasks

GLM 5.2

GLM 5.2 lists tool use across long-running tasks among its strengths; Gemini 4 Carbon does not.

Lowest cost at scale

GLM 5.2

At $1.4/$4.4 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Which should you pick?

A cost-sensitive startup shipping high volume

→ GLM 5.2

At $1.4/$4.4 per 1M tokens it undercuts Gemini 4 Carbon, and on millions of tokens that margin decides the monthly bill.

A team with data-privacy or self-hosting needs

→ GLM 5.2

Open weights let you run it on your own hardware; Gemini 4 Carbon is API-only.

Anyone whose priority is ranked first on the artificial analysis intelligence index v5.0 with 59 at launch (artificial analysis now shows 60)

→ Gemini 4 Carbon

It is specifically built for that.

Anyone whose priority is long-horizon agentic coding

→ GLM 5.2

That is its strongest area.

An enterprise with regional data-residency rules

→ Gemini 4 Carbon or GLM 5.2

Origin (US vs China) affects where data is processed and which compliance regime applies — check the provider's terms for your region.

Gemini 4 Carbon: where it fits

Google's October 28, 2026 limited release for cyber defenders - top of the Artificial Analysis index at launch, priced at $2/$10 introductory, with no public API date yet. Released October 28, 2026 by Google, it is built for ranked first on the Artificial Analysis Intelligence Index v5.0 with 59 at launch (Artificial Analysis now shows 60), google-reported 88.2% on SEC-bench Pro and 54.8% on ExploitGym for vulnerability discovery and exploit validation, google-reported 71.0% on CWE-bench for patching, and introductory $2/$10 per million tokens, matching Gemini 4 Argon, with cached input 95% off.

Its trade-offs are real: limited release: rolling out to a subset of cyber defenders, then trusted partners via the Fairwind Program, with no date for developers or consumers, no public API model listing yet, so most users cannot call it today, introductory pricing rises to $4/$20 afterward, and Google has not said when that happens, and google has not published context or modality specs - the 1M window and modalities shown come from Artificial Analysis and Vals. At $2 in / $10 out per million tokens, it sits in the mid price band.

GLM 5.2: where it fits

An open-weight reasoning model built for long-horizon coding and multi-step agent workflows — strong and cheap. Released June 16, 2026 by Z.ai, it is built for long-horizon agentic coding, project-level software engineering, tool use across long-running tasks, and tops the open-weight intelligence index (SWE-bench Pro 62.1).

Its trade-offs: text-only — no native multimodal input, and new release with a limited third-party track record. At $1.4 in / $4.4 out per million tokens, it sits in the mid price band.

The bottom line for this matchup

The defining split here is open vs. closed. GLM 5.2 gives you weights you control — self-host it, fine-tune it, keep data in-house, pay only for hardware. Gemini 4 Carbon gives you a managed, always-updated API with no infrastructure to run. Teams with GPUs, privacy requirements, or huge volume often favour the open model; teams that want zero ops and the latest capabilities favour the closed one. Capability is close enough that this operational question, not the benchmark, usually decides it.

Want both Gemini 4 Carbon and GLM 5.2 without two subscriptions? LumiChats gives you these plus 40+ models under one ₹69/day pass (about $1/day) — draft with one, cross-check with the other.

See pricing

Frequently asked questions

Is Gemini 4 Carbon or GLM 5.2 better for coding?

Public SWE-Bench figures are not available for either model, so the honest test is your own repository — run an identical real bug through both. By design, Gemini 4 Carbon leans toward ranked first on the artificial analysis intelligence index v5.0 with 59 at launch (artificial analysis now shows 60) while GLM 5.2 leans toward long-horizon agentic coding, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, Gemini 4 Carbon or GLM 5.2?

GLM 5.2 is open-weight, so self-hosting means no per-token fee (you pay for hardware instead), while Gemini 4 Carbon is API-metered at $2/$10 per 1M tokens. For most teams without GPUs, the API model is cheaper to start; at very high volume, self-hosting can win.

Which has the bigger context window?

Both advertise 1M tokens (~1,500 pages). Remember advertised ≠ usable: recall typically degrades before the ceiling.

Can I use both Gemini 4 Carbon and GLM 5.2 together?

Yes — a multi-model platform like LumiChats gives you Gemini 4 Carbon, GLM 5.2 and 40+ others under one ₹69/day pass (about $1/day), so you can draft with one and cross-check with the other instead of buying two subscriptions.

Which is newer, Gemini 4 Carbon or GLM 5.2?

Gemini 4 Carbon — released October 28, 2026, about 4 months after GLM 5.2.

Related comparisons

Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.