GPT-4o-mini vs GLM 4.5 Air

GPT-4o-mini at $0.172 in and $0.690 out and GLM 4.5 Air at $0.149 in and $0.978 out — per million tokens, from the same wallet.

GPT-4o-mini

OpenAI

0.14¢

for a client proposal

$0.172 in · $0.690 out / 1M

128K context · released July 2024

Full page →

GLM 4.5 Air

Z.ai

0.15¢

for a client proposal

$0.149 in · $0.978 out / 1M

131K context · released July 2025

Full page →

Asking all both at once — identical prompt, identical context — costs about 0.29¢ for a typical client proposal.

At a glance

Cheapest input: GLM 4.5 Air at $0.149 per million tokens.
Cheapest output: GPT-4o-mini at $0.690 per million tokens.
Largest context: GLM 4.5 Air at 131K tokens — about 190 pages.

Cost per task

Estimated totals at the rates above. Solid bar is input, lighter bar is output.

Quick code fix

2K in · 500 out

GPT-4o-mini

0.07¢

GLM 4.5 Air

0.08¢

Draft a client proposal from notes

5K in · 800 out

GPT-4o-mini

0.14¢

GLM 4.5 Air

0.15¢

Context-heavy session (Alyph workspace)

155K in · 4K out

GPT-4o-mini

needs 155K ctx

GLM 4.5 Air

needs 155K ctx

Analyze a 50-page legal contract

35K in · 1K out

GPT-4o-mini

0.67¢

GLM 4.5 Air

0.62¢

Large architecture refactor

250K in · 3K out

GPT-4o-mini

needs 250K ctx

GLM 4.5 Air

needs 250K ctx

Solid part of each bar is input tokens, the lighter part is output. Models that don’t fit a task are marked instead of priced.

Cost vs Token Amount

Drag the slider to adjust the split between input and output workload.

80% Input20% Output

GPT-4o-mini

GLM 4.5 Air

Adjust the ratio slider to change how output tokens influence the final price for equivalent workloads.

Pricing

GPT-4o-mini

GLM 4.5 Air

Input / 1M tokens

$0.172

$0.149

Output / 1M tokens

$0.690

$0.978

Cached input / 1M

$0.086

$0.029

Specs

GPT-4o-mini

GLM 4.5 Air

Provider

OpenAI

Z.ai

Released

July 2024

July 2025

Context window

128K

131K

Max output

16K

98K

Input

Text, Images, and Files

Text

Output

Text

Reasoning

Answers directly

Shows its thinking

Knowledge cutoff

2023-10-31

2024-12-31

Try it with real numbers

2K tokens in · 500 tokens out.

GPT-4o-mini

OpenAI

0.07¢

for this task

50% input · 50% output

Full pricing →

GLM 4.5 Air

Z.ai

0.08¢

for this task

38% input · 62% output

Full pricing →

All 2, same prompt and context: 0.15¢. That is the entire cost of the comparison.

Your $5 welcome credit covers about 3,383 of these.

Which should you pick?

For long documents, GLM 4.5 Air has the largest context window here — 131K tokens.

On price, GPT-4o-mini is the cheapest of the two on a typical task, at about 0.14¢.

For images or files, GPT-4o-mini can read them directly; GLM 4.5 Air is text-only.

If you want to watch the model think, GLM 4.5 Air shows reasoning; the other answers directly.

Or don’t pick. Send the identical prompt to all both, read the answers side by side, and keep the winner. How to run a fair bake-off →

GPT-4o-mini pricing →GLM 4.5 Air pricing →Add Lyria 3 Clip Preview Add Grok 4.20

Questions, answered

Which is cheaper, GPT-4o-mini or GLM 4.5 Air?

On a typical client proposal (5K tokens in, 800 out): GPT-4o-mini at 0.14¢; GLM 4.5 Air at 0.15¢. Long prompts can change the order when long-context rates apply.

Which has the largest context window?

GLM 4.5 Air — 131K tokens, about 190 pages.

Can I run GPT-4o-mini and GLM 4.5 Air side by side on Alyph?

Yes — that is what Alyph is built for: the identical prompt with identical context to all 2, answers rendered side by side, billed from one wallet. This exact combination costs about 0.29¢ for a typical task.

Ask both at once

Identical prompt, identical context, answers side by side — about 0.29¢ for a typical client proposal. Free to start, with $5 of credit.