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GLM-4.5 vs o4

A complete head-to-head: pricing, context window, benchmarks, modality coverage, and openness, with a programmatic verdict synthesized from the underlying data.

Updated

GLM-4.5 specs · o4 specs
Verdict by category
  • PriceTie

    Neither model publishes per-token API pricing.

  • Context windowo4

    o4 accepts 200K tokens vs 128K, 1.6× the room for long documents and codebases.

  • BenchmarksTie

    No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores.

  • ModalitiesTie

    Both handle text, vision.

  • OpennessGLM-4.5

    GLM-4.5 ships open weights (MIT); o4 is API-only.

It's a genuine coin-flip between GLM-4.5 and o4: 1 category wins each, with the rest tied. Neither model publishes per-token API pricing. o4 accepts 200K tokens vs 128K, 1.6× the room for long documents and codebases.

No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores. Both target the same set of modalities (text, vision), so the deciding factors are price, context, and raw quality. GLM-4.5 ships open weights (MIT); o4 is API-only.

o4 is the newer of the two, released 5 months after GLM-4.5, which usually means a more recent knowledge cutoff and updated safety post-training. GLM-4.5 is usually picked for chinese llm and open source llm workloads, while o4 sees more deployments in reasoning and math. If pricing matters more than every last benchmark point, run the numbers in the calculator below before committing.

Side-by-side specs

SpecGLM-4.5o4
ProviderOtherOpenAI
ReleasedJul 2025Dec 2025
Modalitiestext, visiontext, vision
Context window128K tokens200K tokens
Max output,,
Input · 1MPricing not publishedPricing not published
Output · 1MPricing not publishedPricing not published
Knowledge cutoff,,
Open weightsYes (MIT)No
API availableYesYes

Pricing at scale

What you'd actually pay at typical workloads. Numbers come from each model's published per-million-token rates.

  • Light usage, 100k in / 50k out per day, vs ,
  • Heavy usage, 1M in / 500k out per day, vs ,
  • RAG workload, 5M in / 200k out per day, vs ,

Light usage, 100k in / 50k out per day: pricing not directly comparable (one or both models are missing public per-token rates). Heavy usage, 1M in / 500k out per day: pricing not directly comparable (one or both models are missing public per-token rates). RAG workload, 5M in / 200k out per day: pricing not directly comparable (one or both models are missing public per-token rates).

Price calculator

Estimated spend for the listed models at your usage. Numbers are derived from each model's published per-million-token rates.

  • GLM-4.5Pricing unavailable
  • o4Pricing unavailable

Benchmarks compared

Only sourced numbers. Where a benchmark is missing for one model we show the available value rather than fabricating the other.

Benchmark scores not yet available. We only publish numbers we can source from official model cards or independent leaderboards, see methodology.
Pick GLM-4.5 if

GLM-4.5 fits when…

  • MIT license
  • Strong Chinese
  • Multimodal
  • Self-hosting and on-prem requirements, open weights (MIT).
Pick o4 if

o4 fits when…

  • Exceptional performance on hard math and reasoning benchmarks
  • Good at multi-step planning and verification
  • Strong scientific reasoning
  • Long-context tasks, handles 200K tokens vs 128K for GLM-4.5.
Don't want either?

Consider DBRX

Databricks' 132B MoE, a notable 2024 open-weight release tuned for enterprise.

See DBRX specsGLM-4.5 vs DBRXo4 vs DBRX

Frequently asked

  • Is GLM-4.5 or o4 cheaper?
    Per-token pricing isn't published for at least one of these models, check each model's spec page for current rates.
  • Which has the larger context window?
    o4 accepts 200K tokens vs 128K for GLM-4.5.
  • Is GLM-4.5 or o4 better for coding?
    Both GLM-4.5 and o4 are competitive on coding benchmarks. See each model's individual spec page for HumanEval and SWE-bench scores where published. For an opinionated pick, consult our Best LLM for Coding ranking.
  • Are either of these models open source?
    GLM-4.5 ships open weights (MIT). o4 is API-only.
  • When were GLM-4.5 and o4 released?
    GLM-4.5 was released by Other on 2025-07-28. o4 was released by OpenAI on 2025-12-15.
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