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Reasoning · 1 checks · max 800 tokens · benched 2026-09-16

GLM 5.3 vs GLM 5.2 vs GLM 5.3 Flash on when does the faster train catch up?

Z Ai models side by side on "When does the faster train catch up?": GLM 5.3 scores 10/10; GLM 5.3 is the cheapest answer scoring 8+ at $0.30 per 1,000 runs. Outputs, checks, judge reasons, latency and cost.

The prompt every model received

System

Think carefully, then give only the final answer in the requested format.

User

Train A leaves a station at 09:10 travelling at a constant 80 km/h. Train B leaves the same station on the same track at 09:40 travelling at a constant 120 km/h in the same direction. How many minutes after 09:10 does train B catch up with train A? Reply with only the whole number of minutes.

Rubric for the judge: The single correct answer 90, with no working shown in the final output.

Side by side

Every cell is one OpenRouter call at temperature 0 with the prompt's token cap and reasoning effort "low" where the model supports it. Cost is usage × the catalogue rate in models.json. Quality is one judge call to anthropic/claude-haiku-4.5 against the prompt's rubric, cached per prompt version.

GLM 5.3

z-ai/glm-5.3

10/10
top judge scorecheapest scoring 8+
Latency
10.7s
Cost
$0.00030
Per 1,000
$0.30

100 in · 37 out (22 reasoning) · 1 words · checks 1/1

  • exact
90

Judge: The output is exactly '90' with no extraneous commentary, matching the rubric requirement perfectly.

GLM 5.2

z-ai/glm-5.2

10/10
Latency
855ms
Cost
$0.00058
Per 1,000
$0.58

100 in · 259 out (256 reasoning) · 1 words · checks 1/1

  • exact
90

Judge: The output is exactly '90' with no extraneous commentary, matching the rubric requirement perfectly.

GLM 5.3 Flash

z-ai/glm-5.3-flash

1/10
Latency
384ms
Cost
$1.6e-5
Per 1,000
$0.02

100 in · 35 out (14 reasoning) · 1 words · checks 0/1

  • exact
120

Judge: The output of 120 is incorrect; the correct answer is 90 minutes.

Frequently asked

What does this prompt test?

Reasoning: The single correct answer 90, with no working shown in the final output. The deterministic checks are exact.

Which model should I pick for this task?

If the judge's bar of 8/10 is good enough for you, GLM 5.3 at $0.30 per 1,000 runs. If you need the top score, GLM 5.3 at $0.30 per 1,000 runs.

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