What is the difference between GLM 5.3 Flash and OpenAI o4-mini?

GLM 5.3 Flash is developed by Zhipu AI while OpenAI o4-mini is developed by OpenAI. You can compare their actual outputs across 15 challenges on Rival to see how they differ in practice.

Which is better, GLM 5.3 Flash or OpenAI o4-mini?

It depends on your use case. GLM 5.3 Flash and OpenAI o4-mini each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 15 challenges so you can judge which fits your needs best.

How much does GLM 5.3 Flash cost compared to OpenAI o4-mini?

GLM 5.3 Flash costs $0.15/M input tokens and OpenAI o4-mini costs $1.1/M input tokens. GLM 5.3 Flash is $0.95/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.

How can I compare GLM 5.3 Flash and OpenAI o4-mini on Rival?

This page shows a side-by-side comparison of GLM 5.3 Flash and OpenAI o4-mini across shared challenges. You can vote on which model produced the better output in a blind duel. Browsing and voting are free. No account is needed to look; signing in only saves your votes and likes.

Updated Aug 2026

GLM 5.3 FlashvsOpenAI o4-mini

GLM 5.3 Flash is cheaper than OpenAI o4-mini at $0.15/M vs $1.1/M input tokens.

GLM 5.3 Flash and OpenAI o4-mini compared across 15 shared prompts
Spec	GLM 5.3 Flash	OpenAI o4-mini
Input price	$0.15/M tokens	$1.1/M tokens
Output price	$0.5/M tokens	$4.4/M tokens
Context window	1.3M tokens	—
Weights	Open	Closed
Free API (OpenRouter)	No	No
Released	Aug 2026	Apr 2025

Our Verdict

GLM 5.3 Flash

OpenAI o4-miniRunner-up

Not enough votes to call it. On the specs, GLM 5.3 Flash has the edge: bigger model tier, newer, bigger context window.

GLM 5.3 Flash costs 8.8x less per token.

Too close to call

API pricing

Cost per 1M tokens

GLM 5.3 Flash

Input

$0.15

7.3× cheaper

Output

$0.50

8.8× cheaper

OpenAI o4-mini

Input

$1.10

Output

$4.40

GLM 5.3 Flash is cheaper on both: 7.3× input, 8.8× output.

Where to run it

31 hosts, cheapest first

GLM 5.3 Flash30 hosts

HostInOutContextUptime

DeepInfrafp4$0.07 in$0.25 out1M99.1% up GMI Cloudfp8$0.07 in$0.25 out1M99.2% up Morph$0.08 in$0.28 out1M100% up InferenceNetfp4$0.09 in$0.28 out1M97.5% up Wafer$0.10 in$0.35 out1M99.7% up OpenInferencefp4$0.10 in$0.50 out1M98.6% up

24 more hosts

Relace$0.11 in$0.36 out1M99.7% up Phalafp8$0.13 in$0.42 out1M99.5% up Novitafp8$0.13 in$0.44 out1M99.4% up StreamLakefp8$0.14 in$0.47 out1M99% up Sail Researchfp8$0.14 in$0.47 out1M99% up AtlasCloudfp8$0.15 in$0.50 out1M99.6% up Basetenfp8$0.15 in$0.50 out1M98.7% up CoreWeavenvfp4$0.15 in$0.50 out1M99.5% up DigitalOcean$0.15 in$0.50 out1M93.7% up Fireworks$0.15 in$0.50 out1M99% up Friendli$0.15 in$0.50 out1M98.7% up Inceptronfp8$0.15 in$0.50 out1M98.2% up io.netfp8$0.15 in$0.50 out262k99.2% up Near AIfp8$0.15 in$0.50 out1M98.9% up Parasailfp8$0.15 in$0.50 out1M98.7% up Rekafp8$0.15 in$0.50 out262k98.9% up SiliconFlowfp8$0.15 in$0.50 out1M99.7% up Together$0.15 in$0.50 out1M99.5% up Venice$0.15 in$0.50 out1M98.8% up Z.aifp8$0.15 in$0.50 out1M96.5% up NextBitfp8$0.18 in$0.60 out1M97.9% up Cloudflare Workers AI$0.30 in$1.00 out1.3M99.8% up Modalfp8$0.45 in$1.50 out1M99.6% up Crusoefp4degraded$0.15 in$0.50 out1M93% up

OpenAI o4-mini1 host

HostInOutContextUptime

OpenAI$1.10 in$4.40 out200k100% up

Per million tokens. Prices and uptime via OpenRouter, checked 22 Sep 2026.

Research

What we learned reading every model

FAQ

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More comparisons

Cost per 1M tokens

31 hosts, cheapest first

What we learned reading every model

Common questions

What is the difference between GLM 5.3 Flash and OpenAI o4-mini?

Which is better, GLM 5.3 Flash or OpenAI o4-mini?

How much does GLM 5.3 Flash cost compared to OpenAI o4-mini?

How can I compare GLM 5.3 Flash and OpenAI o4-mini on Rival?

More comparisons

Against the newest arrivals

Same lab, same size, long tail

Model pages

Cost per 1M tokens

31 hosts, cheapest first

What we learned reading every model

Common questions

What is the difference between GLM 5.3 Flash and OpenAI o4-mini?

Which is better, GLM 5.3 Flash or OpenAI o4-mini?

How much does GLM 5.3 Flash cost compared to OpenAI o4-mini?

How can I compare GLM 5.3 Flash and OpenAI o4-mini on Rival?

More comparisons

Against the newest arrivals

Same lab, same size, long tail

Model pages