Gemini 3.5 Flash-Lite vs Grok 4 Fast

    Comparison

    As of August 20, 2026, Grok 4 Fast is 75% cheaper per million tokens than Gemini 3.5 Flash-Lite. Gemini 3.5 Flash-Lite is $0.30 / $2.50 per million input/output tokens versus Grok 4 Fast at $0.20 / $0.50. Sources: https://ai.google.dev/gemini-api/docs/pricing and https://docs.x.ai/docs/models

    Sources: Gemini API pricing (https://ai.google.dev/gemini-api/docs/pricing); xAI API pricing (https://docs.x.ai/docs/models)

    Gemini 3.5 Flash-Lite

    Google

    $2.80blended / 1M

    Input

    $0.30

    Output

    $2.50

    1M ctx|Proprietary
    75%
    cheaper
    Better value

    Grok 4 Fast

    xAI

    $0.70blended / 1M

    Input

    $0.20

    Output

    $0.50

    2M ctx|Proprietary
    Save $2.10 per million tokens by choosing Grok 4 Fast over Gemini 3.5 Flash-Lite.

    Gemini 3.5 Flash-Lite vs Grok 4 Fast comparison

    Token pricing, specs, and benchmarks side by side

    Metric
    Gemini 3.5 Flash-Lite
    Grok 4 Fast
    Provider
    Provider
    Google
    xAI
    License
    Proprietary
    Proprietary
    Release Date
    2026-07-21
    2025-08-28
    Pricing (per 1M tokens)
    Input Price+50%
    $0.30
    $0.20
    Output Price+400%
    $2.50
    $0.50
    Blended (1M + 1M)
    $2.80
    $0.70
    Model Details
    Context Window
    1M
    2M
    Max Output Tokens
    65.5K
    30K
    Knowledge Cutoff
    2026-03-31
    N/A
    Throughput
    N/A
    90 tok/s
    Benchmarks
    20%
    85.7%
    75.8%
    40.9%
    44.9%
    95%
    10.3%
    5.3%
    74%
    76.5%
    60%
    92%
    83.6%
    60.7%
    0%
    72.3%
    30%
    43.2%
    10%
    93.3%
    26.2%
    43.5%
    70.9%
    39.2%
    85.8%
    21.3%
    47.3%
    72.6%
    Benchmark Wins
    Gemini 3.5 Flash-Lite 4|2 Grok 4 Fast

    Verdict

    Gemini 3.5 Flash-Lite vs Grok 4 Fast: the bottom line

    Grok 4 Fast offers significantly lower pricing, while Gemini 3.5 Flash-Lite leads on benchmark performance. Your choice depends on whether cost efficiency or raw capability matters more for your use case.

    Gemini 3.5 Flash-Lite vs Grok 4 Fast FAQ

    Which is cheaper, Gemini 3.5 Flash-Lite or Grok 4 Fast?

    As of August 20, 2026, Grok 4 Fast is 75% cheaper on blended LLM API pricing. Grok 4 Fast costs $0.20 per million input tokens and $0.50 per million output tokens ($0.70 blended 1M-in + 1M-out). Gemini 3.5 Flash-Lite costs $0.30 / $2.50 per million tokens ($2.80 blended). Sources: https://ai.google.dev/gemini-api/docs/pricing and https://docs.x.ai/docs/models. The cheapest LLM for your app still depends on how many output tokens you generate.

    How much does Gemini 3.5 Flash-Lite vs Grok 4 Fast cost per million tokens?

    Gemini 3.5 Flash-Lite Gemini API pricing is $0.30 input and $2.50 output per million tokens via Google. Grok 4 Fast xAI API pricing is $0.20 input and $0.50 output per million tokens via xAI. Use those four numbers, not ChatGPT Plus or Claude Pro subscription prices, when you are comparing APIs.

    Which is better for coding, Gemini 3.5 Flash-Lite or Grok 4 Fast?

    Gemini 3.5 Flash-Lite has a published SWE-bench Verified score of 75%. Grok 4 Fast does not have that eval on this page yet.

    What is the context window for Gemini 3.5 Flash-Lite vs Grok 4 Fast?

    Gemini 3.5 Flash-Lite supports a 1M token context window, while Grok 4 Fast supports 2M tokens. Grok 4 Fast offers a larger context window. Filling a larger window bills more input tokens, so the cheaper-per-million model can still cost more on long documents.

    Which model performs better on benchmarks, Gemini 3.5 Flash-Lite or Grok 4 Fast?

    Gemini 3.5 Flash-Lite leads on 4 of 6 shared benchmarks versus Grok 4 Fast's 2 wins. Check the comparison table for GPQA Diamond, SWE-bench, MMLU, HLE, and the other evals we track. Token price and benchmark score together are the usual LLM comparison, not either number alone.

    Is Gemini 3.5 Flash-Lite or Grok 4 Fast better for production use?

    Both Gemini 3.5 Flash-Lite and Grok 4 Fast are production API models. For cost-sensitive production traffic, Grok 4 Fast has better economics on the blended 1M-in + 1M-out scale. For maximum capability, weight the benchmark table for your domain. Many production stacks route cheap models for drafts and a frontier model for the hard turn, which is usually cheaper than sending everything to the expensive API.

    Can I switch between Gemini 3.5 Flash-Lite and Grok 4 Fast in my app?

    Yes. Call Gemini 3.5 Flash-Lite through Google and Grok 4 Fast through xAI with separate API keys, or through a gateway that already wraps both. Keep prompts in tokens, not characters, when you estimate the invoice. AnotherWrapper templates can swap providers without rewriting auth and billing.

    How accurate is this Gemini 3.5 Flash-Lite vs Grok 4 Fast pricing data?

    List rates are the latest published Gemini API pricing and xAI API pricing, quoted per million tokens. Official rate sheets: https://ai.google.dev/gemini-api/docs/pricing and https://docs.x.ai/docs/models. Prompt caching, batch APIs, and committed-use discounts can change the invoice. Benchmark scores are from official publications and independent evals, updated as new numbers land.

    What is the output token limit for Gemini 3.5 Flash-Lite and Grok 4 Fast?

    Gemini 3.5 Flash-Lite supports up to 66K output tokens per request, while Grok 4 Fast supports up to 30K output tokens. Output tokens are usually the expensive half of API pricing, so a higher max output cap is a capability, not a discount.

    Which model has better throughput, Gemini 3.5 Flash-Lite or Grok 4 Fast?

    Grok 4 Fast has a measured throughput of approximately 90 tokens/second. Throughput data for Gemini 3.5 Flash-Lite is not yet available. Throughput (tokens per second) and time-to-first-token are why two models with the same per-million-token price can still feel different in chat and agents.

    How do I switch the models in this Gemini 3.5 Flash-Lite vs Grok 4 Fast comparison?

    Use the model pickers at the top of this LLM comparison. Search any model in the index and the URL updates. Open Gemini 3.5 Flash-Lite or Grok 4 Fast from the sidebar for the single-model API pricing page, or go back to the LLM pricing table to sort by cheapest blended cost.

    Gemini 3.5 Flash-Lite vs Grok 4 Fast pricing

    This comparison covers API pricing, context window, throughput, and benchmark scores. Gemini 3.5 Flash-Lite costs $0.30/M input and $2.50/M output. Grok 4 Fast costs $0.20/M input and $0.50/M output.

    Rank both on the LLM leaderboard, SWE-bench, and Humanity's Last Exam.

    The index

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