LLM·Dex

GLM-4.5 vs GPT-5

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 · GPT-5 specs
Verdict by category
  • PriceGPT-5

    GPT-5 publishes pricing ($10.00 / 1M output tokens) while GLM-4.5 does not.

  • Context windowGPT-5

    GPT-5 accepts 400K tokens vs 128K, 3.1× 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.

  • ModalitiesGPT-5

    GPT-5 supports 3 modalities (text, vision, audio) vs 2 for GLM-4.5.

  • OpennessGLM-4.5

    GLM-4.5 ships open weights (MIT); GPT-5 is API-only.

On balance GPT-5 edges ahead, winning 3 of 5 categories against GLM-4.5's 1. GPT-5 publishes pricing ($10.00 / 1M output tokens) while GLM-4.5 does not. GPT-5 accepts 400K tokens vs 128K, 3.1× the room for long documents and codebases.

No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores. They differ in modality coverage, GLM-4.5 handles text, vision while GPT-5 handles text, vision, audio, which can be the deciding factor before you even look at benchmarks. GLM-4.5 ships open weights (MIT); GPT-5 is API-only.

Both shipped within roughly a month of each other in 2025, so they share the same generation of training data and tooling. GLM-4.5 is usually picked for chinese llm and open source llm workloads, while GPT-5 sees more deployments in coding llm and agents. If pricing matters more than every last benchmark point, run the numbers in the calculator below before committing.

Side-by-side specs

SpecGLM-4.5GPT-5
ProviderOtherOpenAI
ReleasedJul 2025Aug 2025
Modalitiestext, visiontext, vision, audio
Context window128K tokens400K tokens
Max output,128K tokens
Input · 1MPricing not published$1.25 / 1M tokens
Output · 1MPricing not published$10.00 / 1M tokens
Knowledge cutoff,2024-09
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 $18.75
  • Heavy usage, 1M in / 500k out per day, vs $188
  • RAG workload, 5M in / 200k out per day, vs $248

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
  • GPT-5$0.625

Benchmarks compared

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

GLM-4.5GPT-5
  • MMLU,91.4
  • HumanEval,96.2
  • GPQA,89.4
  • SWE-bench Verified,74.9
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 GPT-5 if

GPT-5 fits when…

  • Unified model, reasoning routed automatically per query
  • Excellent tool-use and JSON-mode discipline
  • Strong agent performance on SWE-bench Verified
  • Long-context tasks, handles 400K tokens vs 128K for GLM-4.5.
  • Multimodal needs covering audio.
Don't want either?

Consider DBRX

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

Frequently asked

  • Is GLM-4.5 or GPT-5 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?
    GPT-5 accepts 400K tokens vs 128K for GLM-4.5.
  • Is GLM-4.5 or GPT-5 better for coding?
    Both GLM-4.5 and GPT-5 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). GPT-5 is API-only.
  • When were GLM-4.5 and GPT-5 released?
    GLM-4.5 was released by Other on 2025-07-28. GPT-5 was released by OpenAI on 2025-08-07.
Friday digest

The week's AI launches, in your inbox.

One short email every Friday, new models, leaks, and quietly-shipped APIs you missed.