Compare / o3 vs GLM 5.3
o3 vs GLM 5.3
Which is cheaper, which is more capable, and which does better at each kind of work, from 14 results on 3 sources that measured both models.
o3 or GLM 5.3? The short answer
- GLM 5.3 is cheaper: $2.15 against $3.50 per million tokens, 39% less.
- GLM 5.3 scores higher on the Artificial Analysis Intelligence Index: 44.8 against 20.2.
- o3 writes faster: 126 tokens a second against 75.
- On our business benchmarks, GLM 5.3 ranks higher for agents and tool use, reasoning and knowledge, writing and sticking to the facts.
At a glance
| o3 | GLM 5.3 | |
|---|---|---|
| Price per million tokens | $2.00 in · $8.00 out | $1.40 in · $4.40 out |
| Blended (3 in : 1 out) | $3.50 | $2.15 |
| Cheapest host, blended | – | $0.65 (Novita, FP8) |
| Intelligence Index | 20.2 | 44.8 |
| Spring Prompt overall | – | 39 |
| Output speed, tokens a second | 126 | 75 |
| Context window | 200,000 tokens | 1,048,576 tokens |
| Weights | Closed | Open |
| Developer based in | the US | China |
Prices are the developer's list price where we have read it, otherwise the typical host on OpenRouter; see every model's price. Intelligence and speed from Artificial Analysis.
Which is better for what
Each model's rank among models available today, for each kind of work, from our own benchmarks and licensed sources. The better rank is in green.
| Use case | o3 | GLM 5.3 |
|---|---|---|
| Marketing planningPlanning a year of ad spend without overspending | not measured | 16 of 18 |
| Agents and tool useMulti-step tasks with tools: support desks, coding agents, function calls | 13 of 161 | 11 of 161 |
| Professional workReal tasks from banking, consulting and law, business documents and freelance projects | not measured | 15 of 51 |
| Reasoning and knowledgeHard questions across science, maths and general knowledge | 95 of 195 | 24 of 195 |
| WritingWhat people prefer in blind comparisons, and judged writing quality | 49 of 187 | 20 of 187 |
| Sticking to the factsSummarising without inventing things, and factual answers | 91 of 153 | 52 of 153 |
| Speed under pressureGood decisions against a real clock (fast chess) | not measured | 18 of 21 |
Every shared result
| Benchmark | Metric | o3 | GLM 5.3 |
|---|---|---|---|
| Arena (formerly LMArena)reported | OverallArena rating | 1,405 | 1,468 |
| Arena (formerly LMArena)reported | Business, management and financeArena rating | 1,426 | 1,474 |
| Arena (formerly LMArena)reported | Creative writingArena rating | 1,383 | 1,456 |
| Arena (formerly LMArena)reported | Expert promptsArena rating | 1,449 | 1,516 |
| Arena (formerly LMArena)reported | Instruction followingArena rating | 1,403 | 1,480 |
| Arena (formerly LMArena)reported | OverallArena rating | 1,432 | 1,480 |
| Arena (formerly LMArena)reported | Writing, literature and languageArena rating | 1,396 | 1,470 |
| Artificial Analysisreported | Artificial Analysis Intelligence Indexindex score | 20.2 | 44.8 |
| Artificial Analysisreported | GPQA Diamond% of questions | 82.7% | 91.7% |
| Artificial Analysisreported | Humanity's Last Exam% of questions | 20.1% | 42.3% |
| Artificial Analysisreported | Long-context reasoning (AA-LCR)% of questions | 74.7% | 79.7% |
| Artificial Analysisreported | Output speedtokens per second | 126 | 75.2 |
| Artificial Analysisreported | Time to first answer tokenseconds | 3.96 | 29.3 |
| SimpleQA Verified (Epoch AI)reported | Correct answers% of questions | 49.4% | 41.0% |
Bold green marks the better value on that metric. Where a source reports ranges that overlap, the difference may not be meaningful; see the benchmark page for ranges.
Quick answers
Is o3 better than GLM 5.3?
It depends on the task. Among models available today, on our benchmarks and licensed sources, GLM 5.3 ranks higher for agents and tool use, reasoning and knowledge, writing and sticking to the facts.
Which is cheaper, o3 or GLM 5.3?
GLM 5.3 costs $2.15 per million tokens (three input to one output), against $3.50 for o3.
Which is faster, o3 or GLM 5.3?
o3 writes about 126 tokens a second on its usual API, against 75 for GLM 5.3 (Artificial Analysis).
Run o3 and GLM 5.3 on your own prompt
Benchmarks aren't your data. Try both side by side in the playground, with the cost of every answer.