Pricing comparison

o4-mini vs Gemini 3.1 Flash-Lite (preview)

Per-token pricing, full-workload cost ladders, and monthly volume projections. Numbers sourced directly from each provider's rate card.

OpenAI

o4-mini

Input
$1.10 / 1M
Output
$4.40 / 1M
Cached input
$0.275 / 1M
Context
200K
Max output
100K

Google

Gemini 3.1 Flash-Lite (preview)

Input
$0.25 / 1M
Output
$1.50 / 1M
Cached input
$0.025 / 1M
Context
1M
Max output
-

Cost per request

Four common workload shapes, input tokens and a 1:2 output ratio (a standard chat/completion pattern). Long-context surcharges apply automatically where the provider charges them.

ScenarioTokens (in / out)o4-miniGemini 3.1 Flash-Lite (preview)Winner
Short prompt100 / 200$0.0010$0.0003Gemini 3.1 Flash-Lite (preview)
Typical request1,000 / 2,000$0.0099$0.0033Gemini 3.1 Flash-Lite (preview)
Long document10,000 / 5,000$0.0330$0.0100Gemini 3.1 Flash-Lite (preview)
Large prompt100,000 / 10,000$0.1540$0.0400Gemini 3.1 Flash-Lite (preview)

Monthly bill at scale

Projected monthly cost at typical request volume, assuming the "typical request" shape above (1k in, 2k out).

TrafficReq / montho4-miniGemini 3.1 Flash-Lite (preview)Delta
Small SaaS1,000$9.90$3.25Gemini 3.1 Flash-Lite (preview) -$6.65
Growing product10,000$99.00$32.50Gemini 3.1 Flash-Lite (preview) -$66.50
Heavy usage100,000$990.00$325.00Gemini 3.1 Flash-Lite (preview) -$665.00

Which should you use?

For the typical chat-shape request (~1k input, 2k output), Gemini 3.1 Flash-Lite (preview) comes out 205% cheaper. If you're picking one as the default, that's usually the right choice on cost alone.

Gemini 3.1 Flash-Lite (preview) wins on both sides of the bill - cheaper input and cheaper output. If the quality gap is in your favour, there's no cost argument for the other side.

Context window differs: Gemini 3.1 Flash-Lite (preview) holds 1M of input vs 200K on the other side. If you regularly push past the smaller ceiling, the comparison ends there.

Live cost calculator

Type in any token counts - both prices update instantly. Uses base input/output rates (no cache discount, no long-context tier).

o4-mini

$0.0033

per request

Gemini 3.1 Flash-Lite (preview)

$0.0010

per request

Gemini 3.1 Flash-Lite (preview) is $0.0023 cheaper per request (69.7% less).

Try both in the estimator →

Drop your actual prompt in, tokens are counted with the provider's own tokenizer, and the dollar number matches what lands on your invoice.

Frequently asked

Which is cheaper, o4-mini or Gemini 3.1 Flash-Lite (preview)?
On a typical 1,000-input / 2,000-output request, Gemini 3.1 Flash-Lite (preview) costs ~$0.0033 vs ~$0.0099 on o4-mini. Input or output rates can flip the answer for very lopsided workloads - see the cost ladder above.
What's the difference in per-token pricing?
o4-mini charges $1.10 per 1M input tokens and $4.40 per 1M output tokens. Gemini 3.1 Flash-Lite (preview) charges $0.25 / $1.50 per 1M.
Which has the bigger context window?
Gemini 3.1 Flash-Lite (preview) is larger (1M) vs 200K on the other.
Is there a cached-input discount on either?
o4-mini caches at $0.275 per 1M (75% off). Gemini 3.1 Flash-Lite (preview) caches at $0.025 per 1M (90% off). Workloads with repeated static prefixes see the biggest savings.
How fresh is this comparison?
o4-mini was re-verified on 2026-04-06 and Gemini 3.1 Flash-Lite (preview) on 2026-04-06 against each provider's published rate card. Calcis re-checks every row on a rolling schedule and re-deploys when a provider changes pricing.

o4-mini verified 2026-04-06 · Gemini 3.1 Flash-Lite (preview) verified 2026-04-06. Rate cards at OpenAI and Google.