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Model comparison

GLM 5.3 vs GLM 5.3 Flash

Two Z.ai tiers compared on the figures that decide which one a workload actually needs.

Catalog record checked September 3, 2026Individual provider fields may changeEvidence confidence: High — see receipts below

Z.ai

GLM 5.3

Frontier · Open weights

vs

Z.ai

GLM 5.3 Flash

Balanced · Open weights

AI model capability comparison
SpecificationGLM 5.3GLM 5.3 Flash
ProviderZ.aiZ.ai
TierFrontierBalanced
Context window1MWinner: 1.05M
Max output128KWinner: 131K
Input / 1M tokens$1.40Winner: $0.15
Output / 1M tokens$4.40Winner: $0.50
WeightsOpenOpen
Parameters753B total (MoE; active count unpublished)320B total / 18B active (MoE)
Reasoning levelslow, high, maxNot verifiedUnverified
Modalitiestexttext, image, video
Licenseglm-5.3 (custom)MIT
API model idglm-5.3Not publishedUnverified
ReleasedAugust 14, 2026August 26, 2026
Artificial Analysis Intelligence Index [max] (2026-08-14)60Not verifiedUnverified
Artificial Analysis Intelligence Index (2026-08-26)Not verifiedUnverified57
Terminal-Bench 2.1 (2026-08-14)Winner: 88.284.3
DeepSWE 1.1 (2026-08-14)Winner: 66.963.4
Humanity's Last Exam (2026-08-14)Winner: 62.555.3
SWE-bench Verified (2026-09-01)Winner: 95.492

Prices are USD per million tokens at standard rates, excluding batch and caching discounts. Bold indicates the better figure where one is objectively better. Values we could not confirm from the provider are shown as “Not verified” rather than estimated.

Benchmark receipts

  • 2026-09-01: vals.ai SWE-bench Verified leaderboard (independent, mini-swe-agent bash-only); not published by Z.aiReal GitHub issue resolution: does the model's patch pass the hidden tests. Comparability: comparable with caveat — Post-audit vendor claims and pre-audit scores sit on different task trust levels; scaffolding (agent harness, compute budget) also dominates results. Never aggregate across scaffolds.
  • 2026-08-26: Artificial AnalysisComposite index blending reasoning, knowledge, and coding evals into one 0–100 score. Comparability: directly comparable — AA occasionally rebaselines the index scale between snapshots — a score captured on one date is only comparable to same-snapshot scores (check measuredAt).
  • 2026-08-14: Z.ai GLM-5.3 blog + HF model card (vendor, with tools, full set)Agentic terminal work: multi-step tasks executed in a sandboxed shell environment. Comparability: comparable with caveat — Scores across Terminal-Bench major versions (v1 vs v2) are NOT comparable; harness configuration (container, time limits) also shifts results.
  • 2026-08: Z.ai GLM-5.3-Flash blog (vendor, mini-swe-agent, 400K context)Agentic software engineering: pass@1 on real repo tasks with reported cost per completed task. Comparability: directly comparable
  • 2026-08: GLM-5.3-Flash HF model card (vendor, with tools, full set)Agentic terminal work: multi-step tasks executed in a sandboxed shell environment. Comparability: comparable with caveat — Scores across Terminal-Bench major versions (v1 vs v2) are NOT comparable; harness configuration (container, time limits) also shifts results.

Pricing tiers: GLM 5.3: Token API listed at $1.40/$4.40 per MTok from 2026-08-18 (cached input $0.26); Coding Plan access on a points quota. 1M context, 128K max output per official docs; thinking always on. 753B total MoE per the Hugging Face card (active count unpublished). · GLM 5.3 Flash: $0.15/$0.50 per MTok is the standard first-party and third-party rate (Z.ai docs; GMI, Novita, Together). A 50% promo tier runs $0.075/$0.25 — confirm which rate your account quotes.

FrontierOpen weightsRecord checked September 3, 2026

GLM 5.3

GLM 5.3 is Zhipu's flagship (~753B MoE), near the top of the leaderboards, and the current GLM Coding Plan default.

Best for

  • Coding Plan subscribers
  • Long-horizon coding
  • Chinese + English

Watch out

Open weights dropped 2026-08-28 under Z.ai's custom glm-5.3 licence (not a standard open-source licence — review before commercial use; secondary coverage says >$10B-revenue providers need a security review). 5.2/5.1 Coding Plan requests route to 5.3.

BalancedOpen weightsRecord checked September 3, 2026

GLM 5.3 Flash

GLM 5.3 Flash is Z.ai's natively multimodal open-weight workhorse — 1M context, hybrid sparse/linear attention, near-flagship Intelligence Index at a fraction of the cost.

Best for

  • Cost-efficient long-context
  • Multimodal input
  • Coding agents

Watch out

Self-hosting needs ~186GB GPU memory at 4-bit (multi-GPU). Third-party hosts charge more than Z.ai's own API.

When the cheaper one wins

GLM 5.3 Flash is cheaper on output at $0.50 per million tokens against $4.40 for GLM 5.3 — about 8.8×. Use the cheaper tier for classification, extraction, summarisation, and any task where the expensive model’s extra score does not change the accepted output. The expensive one only pays if your hardest task actually fails on the cheap tier. These are standard-tier API rates, excluding batch and cache discounts.

Run the model picker

Evidence confidence: High

How strong and complete the evidence behind this comparison is — not a prediction of which model is better.

  • Pricing verified on both sides — Input and output rates are verified for both models.
  • 4/5 core specs verified on both sides — Not published for at least one side: reasoning levels.
  • 5 shared named benchmarks with differing scores — Measured on: Artificial Analysis Intelligence Index, Terminal-Bench 2.1, DeepSWE 1.1, Humanity's Last Exam, SWE-bench Verified.
  • Verified within the last 90 days — Newest catalog check was 8 days ago.
  • Both models carry source citations — Each side has at least two catalog sources on record.

Source receipts

Each catalog figure was checked against the provider or an independent second source on the date shown.

Related comparisons

Diving deeper on one model? GLM 5.3 · GLM 5.3 Flash

Common questions

GLM 5.3 vs GLM 5.3 Flash

Answered from the verified figures on this page rather than general guidance.

Is GLM 5.3 or GLM 5.3 Flash cheaper for input?

GLM 5.3 Flash is cheaper at $0.15 per million input tokens, against $1.40 for GLM 5.3 — roughly 9.3× the price. Output tokens usually dominate a real bill, so weigh the output rate more heavily than the input rate. These are base rates; GLM 5.3 has tiered pricing: Token API listed at $1.40/$4.40 per MTok from 2026-08-18 (cached input $0.26); Coding Plan access on a points quota. 1M context, 128K max output per official docs; thinking always on. 753B total MoE per the Hugging Face card (active count unpublished). GLM 5.3 Flash has tiered pricing: $0.15/$0.50 per MTok is the standard first-party and third-party rate (Z.ai docs; GMI, Novita, Together). A 50% promo tier runs $0.075/$0.25 — confirm which rate your account quotes.

Is GLM 5.3 or GLM 5.3 Flash cheaper for output?

GLM 5.3 Flash is cheaper at $0.50 per million output tokens, against $4.40 for GLM 5.3 — roughly 8.8× the price. Output tokens usually dominate a real bill, so weigh the output rate more heavily than the input rate. These are base rates; GLM 5.3 has tiered pricing: Token API listed at $1.40/$4.40 per MTok from 2026-08-18 (cached input $0.26); Coding Plan access on a points quota. 1M context, 128K max output per official docs; thinking always on. 753B total MoE per the Hugging Face card (active count unpublished). GLM 5.3 Flash has tiered pricing: $0.15/$0.50 per MTok is the standard first-party and third-party rate (Z.ai docs; GMI, Novita, Together). A 50% promo tier runs $0.075/$0.25 — confirm which rate your account quotes.

Which has the larger context window, GLM 5.3 or GLM 5.3 Flash?

GLM 5.3 Flash accepts 1.05M tokens against 1M for GLM 5.3. This only matters if you routinely send very long documents or large codebases.

Should I use GLM 5.3 or GLM 5.3 Flash?

GLM 5.3 is the frontier tier and GLM 5.3 Flash the balanced tier. The useful question is whether your hardest task actually fails on the cheaper one — most production volume such as classification, extraction and summarisation does not.

Next step

Choosing between them

The verified figures that separate this pair, computed from the catalog rather than restated boilerplate.

  • Input price: GLM 5.3 Flash costs $0.15 per 1M tokens versus $1.40 for GLM 5.3 — a 9.3x difference at the headline tier.
  • Context: GLM 5.3 Flash takes 1.05M against 1M for GLM 5.3 — only decisive if your prompts approach the smaller window.
  • Measured capability: GLM 5.3 leads Artificial Analysis Intelligence Index 60 to 57 (measured 2026-08-14).
  • Positioning: GLM 5.3 sits in the frontier tier, GLM 5.3 Flash in the balanced tier — most production volume (classification, extraction, summarisation) does not need the pricier tier.
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