GPT 4o pricing for unit test generation

Quick start

Call GPT 4o with the OpenAI Python SDK:

from openai import OpenAI

client = OpenAI()
response = client.chat.completions.create(
    model="gpt-4o",
    max_tokens=5000,
    messages=[{"role": "user", "content": "Your prompt here"}]
)
# Cost: ~$0.0575 per call at standard rates
# Input:  $2.50/MTok
# Output: $10.00/MTok

How GPT 4o compares on cost

Per-call cost for all models scoring 50+ on unit test generation benchmarks. Hover for details.

Cheapest viable option: Claude Sonnet 5 at $0.0560/call (3% less, 93/100 quality).

What drives unit test generation cost

Test generation is the rare code task where input and output are both large: you send the function under test plus its dependencies, and get back a full suite of cases. Expect 3K in, 5K out. Because the source file rarely changes between runs, cache reads pay off faster here than in almost any other use case: the same file gets resent every time you regenerate a suite.

For GPT 4o specifically, that means output tokens cost 4.0x more than input, at $10.00 vs $2.50 per MTok. At this use case’s 3,000/5,000 token split, output accounts for 87% of the $0.0575 per-call cost.

GPT 4o quality benchmarks for unit test generation

Benchmark data for unit test generation is pending for GPT 4o. Test against your own evaluation suite before moving to production.

Performance across all task types

GPT 4o scores by task type. Unit Test Generation highlighted.

Confidence scores are a third-party benchmark snapshot from week 29 of 2026. This snapshot is 10 weeks old, so treat the scores as directional and validate against your own evals.

About GPT 4o

Backfilled on 2026-09-23. Prices confirmed by the provider pricing page and the LiteLLM cross-check. Release date not published in a machine-readable source. Not yet benchmarked, so never recommended.

Other models from GPT

You can compare GPT 4o head-to-head against any other model on our model comparison pages, or track how pricing has changed over time on the pricing history tracker.

Frequently asked questions