Which model is better: GLM-5.3-Flash or GPT-4.5?

**GLM-5.3-Flash decisively outperforms GPT-4.5 across pricing, speed, and coding capabilities.** It is 99.8% cheaper, costing $0.12 versus $75.00 for input and $0.40 versus $150.00 for output per million tokens. Additionally, GLM-5.3-Flash delivers an ultra-fast 90ms TTFT (760ms faster) and leads coding with 52.8% on SWE-bench versus 38.0% for GPT-4.5.
Verified daily via automated API latency tests and official documentation.

Verified Performance & Unit Economics Delta

Daily synchronized metrics from synthetic latency endpoints and benchmark evaluations.

Metric / Dimension GLM-5.3-Flash GPT-4.5 Net Delta / Advantage
Input Cost / 1M Tokens $0.12 $75.00 GLM-5.3-Flash is 625.0x cheaper
Output Cost / 1M Tokens $0.40 $150.00 GLM-5.3-Flash (99.7% lower)
Prompt Cache Read / 1M $0.030 $37.500 GLM-5.3-Flash is 1250.0x cheaper
Prompt Cache Write / 1M $0.12 $75.00 GLM-5.3-Flash is 625.0x cheaper
Avg TTFT Response Latency 90ms 850ms GLM-5.3-Flash (+760ms faster)
SWE-bench Verified (Coding) 52.8% 38% GLM-5.3-Flash (+14.8% lead)
Inference Value Score (IVR) 77.8 / 100 22.1 / 100 GLM-5.3-Flash (+55.7 pts)

Interactive Monthly Token Economics & ROI Forecaster

Model your expected production workload across prompt (input) and completion (output) tokens with prompt caching economics.

Live Calculation Engine
10.0M Tokens
100K 50M 250M 500M+
2.5M Tokens
100K 10M 50M 100M+

Estimated Monthly Spend

GLM-5.3-Flash $2.20

$0.12/1M in · $0.40/1M out

Prompt Cache: $0.030/1M read · $0.12/1M write

GPT-4.5 $1,125.00

$75.00/1M in · $150.00/1M out

Prompt Cache: $37.500/1M read · $75.00/1M write

Projected Monthly Cost Reduction
$1,122.80 / mo
(99.8% lower cost with GLM-5.3-Flash)
A

When to Choose GLM-5.3-Flash

Choose GLM-5.3-Flash when you need Sub-100ms ultra-fast inference model designed for real-time customer support, document classification, and agentic workflows. and have an infrastructure budget aligned with $0.12/1M tokens.

B

When to Choose GPT-4.5

Choose GPT-4.5 when you need Deep world-knowledge synthesis, high-EQ conversational nuance, and long-form creative generation requiring massive pretraining breadth. and prioritize OpenAI ecosystem integration at $75.00/1M tokens.

Related Questions & Decision Factors

Which is cheaper: GLM-5.3-Flash or GPT-4.5?

GLM-5.3-Flash is cheaper at $0.12/1M input tokens compared to $75.00/1M for GPT-4.5.

Which model has lower latency: GLM-5.3-Flash or GPT-4.5?

GLM-5.3-Flash delivers faster response times with an average TTFT of 90ms vs 850ms for GPT-4.5.

When should you choose GLM-5.3-Flash?

Choose GLM-5.3-Flash when you need Sub-100ms ultra-fast inference model designed for real-time customer support, document classification, and agentic workflows. and have an infrastructure budget aligned with $0.12/1M tokens.

When should you choose GPT-4.5?

Choose GPT-4.5 when you need Deep world-knowledge synthesis, high-EQ conversational nuance, and long-form creative generation requiring massive pretraining breadth. and prioritize OpenAI ecosystem integration at $75.00/1M tokens.

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