Gemini 3.8 Flash vs Grok 4.5
Grok 4.5 was superseded by Grok 4.7. The grades below are the last ones measured, so read them as history rather than as this week's board. See the current roster.
Both grade C- overall. Grok 4.5 is about 1.8x cheaper per task. By suite, real-world issues is even at C- and vibe coding is even at C-. Both agents run the same private suite cut headless through their own tools, each on its own subscription.Measured
Each agent graded on the same private suites, running headless through its own tools. Advantages are oriented so a win is a win, whichever way the metric runs.
Verdict: Grok 4.5 vs Gemini 3.8 Flash
Both grade C- overall. By suite: real-world issues is even at C- (60% vs 60% capability); vibe coding is even at C- (56% vs 59% capability). Only Gemini 3.8 Flash has run spec planning. Gemini 3.8 Flash used 23.7% of Google AI Pro's weekly limit per pass, $0.057 per task at the listed price. Grok 4.5 used 6.9% of SuperGrok's weekly limit per pass, $0.032 per task at the listed price. Per task, Grok 4.5 is about 1.8x cheaper ($0.032 vs $0.057). Grok 4.5 is faster on real-world issues: a median task takes 3m 9s against 5m 21s. Both finished every task on it.
Changed since the previous graded week: Gemini 3.8 Flash: real-world issues F to C-, real-world issues usage 18.0% to 21.9% of the weekly limit, spec planning usage 2.0% to 1.8% of the weekly limit, vibe coding D+ to C-, vibe coding usage 1.2% to 1.1% of the weekly limit; Grok 4.5: real-world issues usage 8.0% to 6.9% of the weekly limit.
| Dimension | Gemini 3.8 Flash | Grok 4.5 | Advantage |
|---|---|---|---|
| Capability | 60% | 60% | Even |
| Median task time | 5m 21s | 3m 9s | 2m 11s faster (Grok 4.5 leads) |
| Approx. task cost | $0.067 / task | $0.032 / task | $0.036 / task lower (Grok 4.5 leads) |
Gemini 3.8 Flash: 21.9% of Google AI Pro (131.3% / 5h, 21.9% / 1w) per run. Its weekly limit holds 6 of the week's 33.6 5h windows. Grok 4.5: 6.9% of SuperGrok (6.9% / 1w) per run. Each figure is a share of that agent's own plan, so there is no delta to draw.
Only Gemini 3.8 Flash has run this suite, so there is no head-to-head yet.
| Dimension | Gemini 3.8 Flash | Grok 4.5 | Advantage |
|---|---|---|---|
| Capability | 56% | 59% | +3% (Grok 4.5 leads) |
| Median task time | 7m 51s | 3m 40s | 4m 11s faster (Grok 4.5 leads) |
| Approx. task cost | $0.048 / task | $0.031 / task | $0.018 / task lower (Grok 4.5 leads) |
Gemini 3.8 Flash: 1.1% of Google AI Pro (6.3% / 5h, 1.1% / 1w) per good solve. Its weekly limit holds 6 of the week's 33.6 5h windows. Grok 4.5: 0.4% of SuperGrok (0.4% / 1w) per good solve. Each figure is a share of that agent's own plan, so there is no delta to draw.
Grades and deltas are comparable only within a suite version. See methodology.
Frequently asked questions
Which is better for coding, Gemini 3.8 Flash or Grok 4.5?
They are even on our ladder: both clear tier 4 of 5 at 60% capability on real-world@v3, our private suite of real-world coding problems. Latest measurement 2026-09-27.
Which is cheaper per task, Gemini 3.8 Flash or Grok 4.5?
Gemini 3.8 Flash used 23.7% of Google AI Pro's weekly limit per pass, $0.057 per task at the listed price. Grok 4.5 used 6.9% of SuperGrok's weekly limit per pass, $0.032 per task at the listed price. Per task, Grok 4.5 is about 1.8x cheaper ($0.032 vs $0.057).