LLM prices / Google / Gemini 3.1 Flash-Lite
Google API · prices checked Oct 23, 2026
Gemini 3.1 Flash-Lite API pricing
Short answerGemini 3.1 Flash-Lite costs $0.25 per 1M input tokens and $1.5 per 1M output tokens on the Google API (standard price, checked Oct 23, 2026). A typical chatbot reply (1,500 tokens in, 400 out) costs $0.0010, so 1,000 replies a day is about $29.25 a month and 1M replies is $975. That makes it #5 cheapest of the 29 current models for that job.
Best for
- High-volume simple jobs (support chat, tagging, extraction): #5 cheapest of 29 current models for a chatbot reply.
- Long repeated prompts (agents, RAG with a fixed prefix): cached input bills at 10% of the normal input price.
- Bulk jobs that can wait: the batch API bills input at 50% of the standard price.
- Whole codebases or contracts in one prompt: 1.05M tokens of context.
- Reading more than text: takes image, video, audio, pdf input.
Skip if
- No price or spec red flags in the data.
Rules: Best for = cheapest quarter of current models for a chatbot reply, top 3 on one of our 8 jobs, cache reads at 15% or less of input, batch at 60% or less, 1M+ context, non-text inputs. Skip if = not current on the provider's page, priciest quarter, text only, no cache or batch price, a long-prompt surcharge, preview, under 200K context, no tool calling. Price and spec facts only; we don't score answer quality.
What your volume costs
Pick a job and a monthly volume. Same prices as everything on this page; caching and batch applied where they make it cheaper.
Cost per task, 8 jobs
Per 1,000 requests and per month at a typical volume, billed the cheapest way the price list allows. The rank is among current models that fit the job.
| Job (links to the cheapest model for it) | Per 1,000 | A month | Rank among fits |
|---|---|---|---|
| Chatbota 1,500-token prompt (system prompt plus the conversation so far) and a 400-token reply | $0.97standard price | $29.25at 30,000 a month | #5 of 29 |
| RAG (answer from your docs)6,000 tokens of retrieved passages plus the question, and a 500-token answer | $2.25standard price | $67.50at 30,000 a month | #4 of 29 |
| Coding agent40,000 tokens of repo context and history, 30,000 of them repeated from the last step and billed at the cache-read price, 2,000 tokens out, tool calling required | $6.25with the repeated 30,000 tokens billed at the cache-read price | $18.75at 3,000 a month | #5 of 29 |
| Tool-using agent12,000 tokens of instructions, tool definitions and history, 10,000 of them repeated from the last step and cached, 600 tokens out, tool calling required | $1.65with the repeated 10,000 tokens billed at the cache-read price | $16.50at 10,000 a month | #5 of 29 |
| Vision (read an image)one image counted as 1,000 input tokens plus a 300-token question, and a 300-token answer. Providers count image tokens differently, so treat vision costs as a rough guide | $0.78standard price | $7.75at 10,000 a month | #5 of 28 |
| Translationa 1,000-token passage in and about 1,100 tokens out (translations run a little longer than the source) | $1.90standard price | $19.00at 10,000 a month | #5 of 29 |
| Batch extraction2,000 tokens per record in and 300 tokens of JSON out, through the batch API where there is one (results within 24 hours) | $0.47through the batch API | $47.50at 100,000 a month | #4 of 29 |
| Summarize long documentsa 20,000-token document in and an 800-token summary out | $6.20standard price | $6.20at 1,000 a month | #4 of 29 |
Cheaper and pricier alternatives
The current models just below and just above Gemini 3.1 Flash-Lite on the cost of 1,000 chatbot replies, with what differs. Price only, not quality.
Cheaper
- DeepSeek Flash $0.930.95x the cost of a chatbot reply, DeepSeek, 1M context vs 1.05M, takes image too.
- GPT-5.6 Luna $0.780.80x the cost of a chatbot reply, OpenAI, 1.05M context vs 1.05M, takes image too.
- Claude Haiku 5.5 $0.350.36x the cost of a chatbot reply, Anthropic, 1M context vs 1.05M, takes image too.
Pricier
- Gemini 3.5 Flash-Lite $1.451.49x the cost of a chatbot reply, same provider.
- Gemini 3 Flash Preview $1.952.00x the cost of a chatbot reply, same provider.
- Gemini 3.8 Flash $2.622.69x the cost of a chatbot reply, same provider.
Every price tier
| Input | $0.25 per 1M tokens |
| Output | $1.5 per 1M tokens |
| Cache read (hit) | $0.025 (10% of the input price) |
| Batch API | $0.125 input / $0.75 output |
| Flex tier | $0.125 input / $0.75 output |
| Priority tier | $0.45 input / $2.7 output |
| API model id | gemini-3.1-flash-lite |
| Status on the pricing page | listed |
Provider notes: prices are the Paid Tier text-token prices; explicit cache storage 1 USD per 1M tokens per hour; audio input is priced higher; see page
Model facts from Google
| Context window | 1,048,576 tokens |
| Max output | 65,536 tokens |
| Input types | text, image, video, audio, pdf |
| Tool calling | yes |
| Lifecycle | current |
Source: https://ai.google.dev/gemini-api/docs/models/gemini-3.1-flash-lite, checked Oct 24, 2026.
The 6 classic workloads
Per 1,000 requests at the standard price. "With caching" bills the repeated part of the prompt at the cache-read price (cache writes not counted); "via batch" uses the batch API price. Run your own token counts in the LLM API cost calculator.
| Workload | Gemini 3.1 Flash-Liteper 1,000 requests |
|---|---|
| Chatbot replya 1,500-token prompt (1,000 of it a fixed system prompt) and a 400-token answer | $0.97$0.75 with caching |
| Answer from your docs (RAG)6,000 tokens of retrieved context plus the question, a 500-token answer | $2.25$2.02 with caching |
| Summarize a long documenta 20,000-token document in, an 800-token summary out | $6.20$5.98 with caching |
| Coding agent step40,000 tokens of repo context and history (30,000 of it repeated from the last step), 2,000 out | $13.00$6.25 with caching |
| Batch extraction2,000 tokens per record in, 300 tokens of JSON out, sent through the batch API where there is one | $0.95$0.47 via batch |
| Long-document Q&Aa 150,000-token contract or codebase in one prompt, a 1,000-token answer | $39.00 |
What the numbers say
- Output costs 6x input on Gemini 3.1 Flash-Lite, so for answer-heavy jobs the output price drives the bill; for document-heavy jobs (RAG, summaries, agents) input does.
- Caching matters: a coding-agent step that rereads 30,000 cached tokens costs 52% less than the same step uncached ($6.25 vs $13.00 per 1,000 steps, cache writes not counted). How to stop paying twice for repeated prompts: LLM semantic cache.
- Among 10 listed Google models it is the #2 cheapest for a chat reply.
Every listed Google model, cheapest first
Same chatbot workload, 1,000 replies.
| Model | Input / 1M | Output / 1M | 1,000 chat replies |
|---|---|---|---|
| Gemini 2.5 Flash-Litelimited access | $0.1 | $0.4 | $0.31 |
| Gemini 3.1 Flash-Lite | $0.25 | $1.5 | $0.97 |
| Gemini 3.5 Flash-Lite | $0.3 | $2.5 | $1.45 |
| Gemini 2.5 Flashlimited access | $0.3 | $2.5 | $1.45 |
| Gemini 3 Flash Preview | $0.5 | $3 | $1.95 |
| Gemini 3.8 Flash | $0.75 | $3.75 | $2.62 |
| Gemini 3.6 Flash | $0.75 | $3.75 | $2.62 |
| Gemini 2.5 Prolimited access | $1.25 | $10 | $5.88 |
| Gemini 4 Argon | $2 | $10 | $7.00 |
| Gemini 3.1 Pro Preview | $2 | $12 | $7.80 |
Closest price from other providers
The current model from each other provider whose chatbot-reply cost is nearest. Price only: we do not rank quality here.
| Model | Input / 1M | Output / 1M | 1,000 chat replies | vs Gemini 3.1 Flash-Lite |
|---|---|---|---|---|
| Claude Haiku 5.5Anthropic | $0.1 | $0.5 | $0.35 | 0.36x |
| GPT-5.6 LunaOpenAI | $0.2 | $1.2 | $0.78 | 0.80x |
| DeepSeek FlashDeepSeek | $0.3 | $1.2 | $0.93 | 0.95x |
Price history
- Oct 23, 2026: Gemini 3.1 Flash-Lite added to the table: $0.25 input / $1.5 output per 1M tokens.
- Checked against the provider page on 1 date: Oct 23, 2026.
Every change we record is on the LLM price changelog.
Sources
- Google API pricing: https://ai.google.dev/gemini-api/docs/pricing, checked Oct 23, 2026.
- Context, inputs and lifecycle: https://ai.google.dev/gemini-api/docs/models/gemini-3.1-flash-lite, checked Oct 24, 2026.
- Dataset: llm-prices (every row names its page and check date) and /llm/prices.csv.
Prices change often. If one is out of date, email matt@tensorust.com and we will fix it.