o4-mini vs GPT-3.5 Turbo
Side-by-side comparison of o4-mini (OpenAI) and GPT-3.5 Turbo (OpenAI). Exact API pricing per million tokens, context windows, output speed, and total cost on real-world prompts.
Specifications
| Spec | o4-mini | GPT-3.5 Turbo |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Model id | o4-mini | gpt-3.5-turbo |
| Input price (per 1M tokens) | $1.10 | $0.50 |
| Output price (per 1M tokens) | $4.40 | $1.50 |
| Context window | 200,000 | 16,385 |
| Output speed (tokens/sec) | ~80 | ~150 |
| Tokenizer encoding | o200k_base | cl100k_base |
Cost on real prompts
Total cost = (input tokens × input price) + (output tokens × output price). Numbers below use the exact pricing tables published by each provider.
| Scenario | Input | Output | o4-mini | GPT-3.5 Turbo | Cheaper |
|---|---|---|---|---|---|
| Short question + answer | 50 | 150 | $0.000715 | $0.00025 | GPT-3.5 Turbo |
| Code review on one file | 500 | 1,500 | $0.007150 | $0.002500 | GPT-3.5 Turbo |
| Long document summary | 5,000 | 500 | $0.007700 | $0.003250 | GPT-3.5 Turbo |
| Heavy reasoning task | 2,000 | 8,000 | $0.037400 | $0.013000 | GPT-3.5 Turbo |
| Full codebase analysis | 50,000 | 10,000 | $0.099000 | $0.040000 | GPT-3.5 Turbo |
Want the exact cost for your prompt instead of these examples? Open the cost calculator pre-loaded with both models →
When to pick which
Heuristics derived from the spec table above. Always validate on your own prompts before committing — these are starting points, not verdicts.
Pick o4-mini for
- •tasks needing a larger context window — o4-mini fits 12x more tokens than gpt-3.5-turbo
- •complex multi-step reasoning (math, debugging, planning) — o4-mini uses chain-of-thought internally
Pick GPT-3.5 Turbo for
- •output-heavy workloads — gpt-3.5-turbo is meaningfully cheaper per output token
- •input-heavy workloads — gpt-3.5-turbo is cheaper per input token
- •latency-sensitive UX — gpt-3.5-turbo streams faster (~150 vs ~80 tok/s)
Switching between them
For most use cases, switching providers means updating the model id and the request shape if the providers differ. Within the same provider, it's usually a single-line change.
From o4-mini to GPT-3.5 Turbo
# Before
model = "o4-mini"
# After
model = "gpt-3.5-turbo" If the providers differ (OpenAI vs OpenAI), you'll also need to swap the SDK / endpoint URL. Cross-provider migrations usually take 30 minutes to a few hours depending on how many features (streaming, function calling, tool use) you depend on.
Calculate cost on your own prompt
The examples above use generic input/output ratios. For an exact comparison, paste your real prompt into the calculator — it counts tokens with the right tokenizer for each model and shows side-by-side cost.
Open the calculator with both models →