Choose Google: Gemma 4 31B (batch) if…
- you generate long outputs in one go — up to 236K tokens (about 176,900 words) per response
- you want the newer model — released 2026-04-02, 8 months after the other
Neither wins outright: Google: Gemma 4 31B (batch) is the pick when you generate long outputs in one go, OpenAI: GPT-5 Nano when cost matters at scale.
| Spec | Google: Gemma 4 31B (batch) | OpenAI: GPT-5 Nano |
|---|---|---|
| Provider | OpenAI | |
| Input price (per 1M tokens) | $0.39 | $0.05 |
| Output price (per 1M tokens) | $0.97 | $0.40 |
| Blended price (3:1 input/output) | $0.53 | $0.14 |
| Cheaper than … of all models we track | 52% | 75% |
| Context window | 262K tokens (~393 pages) | 400K tokens (~600 pages) |
| Larger context than … of all models | 48% | 63% |
| Max output per response | 236K tokens (~176,900 words) | 128K tokens (~96,000 words) |
| Input types | image, text, video | text, image, file |
| Output types | text | text |
| Free variant | No | No |
| Listed since | 2026-04-02 | 2025-08-07 |
Monthly cost at list price for five common workloads. Token counts per unit are stated so you can scale them to your own traffic. A workload that does not fit a model's context window is marked rather than priced.
| Workload (per month) | Google: Gemma 4 31B (batch) | OpenAI: GPT-5 Nano | Difference |
|---|---|---|---|
| Customer-support chatbot 50,000 conversations — each a 6-turn conversation (1,500 in / 400 out tokens) | $48.65 | $11.75 | OpenAI: GPT-5 Nano saves $36.90 |
| RAG search over documents 20,000 questions — each a question answered from ~8 retrieved passages (6,000 in / 500 out tokens) | $56.50 | $10.00 | OpenAI: GPT-5 Nano saves $46.50 |
| Coding / tool-using agent 2,000 tasks — each a multi-step task with tool calls and file context (60,000 in / 6,000 out tokens) | $58.44 | $10.80 | OpenAI: GPT-5 Nano saves $47.64 |
| Batch summarisation 10,000 documents — each a 6,000-word report summarised to a page (8,000 in / 600 out tokens) | $37.02 | $6.40 | OpenAI: GPT-5 Nano saves $30.62 |
| Long-document analysis 500 documents — each a 150-page contract or codebase read in one pass (100,000 in / 2,000 out tokens) | $20.47 | $2.90 | OpenAI: GPT-5 Nano saves $17.57 |
| Capability | Google: Gemma 4 31B (batch) | OpenAI: GPT-5 Nano | What it lets you do |
|---|---|---|---|
| Tool / function calling | ✓ Yes | ✓ Yes | call your APIs and run agent loops |
| Structured output (JSON schema) | ✓ Yes | ✓ Yes | return JSON that validates against your schema |
| Reasoning / thinking mode | ✓ Yes | ✓ Yes | spend extra tokens thinking before answering hard problems |
| Image input | ✓ Yes | ✓ Yes | read screenshots, charts and scanned pages |
| Audio input | — | — | take speech or audio directly |
| File / PDF input | — | ✓ Yes | accept documents without your own parsing step |
| Image output | — | — | generate images, not just text |
| Built-in web search | — | ✓ Yes | answer from live web results |
| Seed (reproducible sampling) | — | ✓ Yes | repeat a generation for tests and evals |
| Log-probabilities | — | — | read token confidence for classification and scoring |
From each model's published parameters and input/output types. “—” means not advertised, not proven absent.
Neither wins outright: Google: Gemma 4 31B (batch) is the pick when you generate long outputs in one go, OpenAI: GPT-5 Nano when cost matters at scale. In short: Google: Gemma 4 31B (batch) when you generate long outputs in one go, you want the newer model; OpenAI: GPT-5 Nano when cost matters at scale, you need to fit long inputs in one request, you need file / PDF input, you need built-in web search, you need seed (reproducible sampling).
OpenAI: GPT-5 Nano is cheaper: $0.14 vs $0.53 per 1M tokens at a typical 3:1 input/output mix, 74% less. For 50,000 support conversations a month that is $11.75 against $48.65.
Google: Gemma 4 31B (batch) costs $0.39 per 1M input tokens and $0.97 per 1M output tokens; OpenAI: GPT-5 Nano costs $0.05 input and $0.40 output. Output tokens are billed separately, so long answers shift the gap.
OpenAI: GPT-5 Nano: 400K tokens, about 600 pages, against 262K (about 393 pages) for Google: Gemma 4 31B (batch).
Tool calling — Google: Gemma 4 31B (batch): yes, OpenAI: GPT-5 Nano: yes. JSON-schema structured output — Google: Gemma 4 31B (batch): yes, OpenAI: GPT-5 Nano: yes.
Yes, both accept image input.
No free variant is listed for either; both are pay-per-token.
Google: Gemma 4 31B (batch) can write up to 236K tokens (about 176,900 words) per response; OpenAI: GPT-5 Nano up to 128K (about 96,000 words).
Google: Gemma 4 31B (batch) was listed on 2026-04-02; OpenAI: GPT-5 Nano on 2025-08-07.
Gemma 4 31B Instruct is Google DeepMind's 30.7B dense multimodal model supporting text and image input with text output. Features a 256K token context window, configurable thinking/reasoning mode, native function...
Full Google: Gemma 4 31B (batch) specs →GPT-5-Nano is the smallest and fastest variant in the GPT-5 system, optimized for developer tools, rapid interactions, and ultra-low latency environments. While limited in reasoning depth compared to its larger...
Full OpenAI: GPT-5 Nano specs →