Claude Haiku 4.5 vs GPT-5.6 Sol
GPT-5.6 Sol was superseded by GPT-6.1 Sol. The grades below are the last ones measured, so read them as history rather than as this week's board. See the current roster.
GPT-5.6 Sol leads overall, C- to F. Claude Haiku 4.5 is about 3.0x cheaper per task. By suite, GPT-5.6 Sol takes real-world issues (C- to D-) and spec planning (C+ to F). Take Claude Haiku 4.5 anyway when you want the side that is cheaper per task and faster on real-world issues.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: GPT-5.6 Sol vs Claude Haiku 4.5
GPT-5.6 Sol leads overall, C- to F. By suite: GPT-5.6 Sol takes real-world issues, C- to D- (60% vs 37% capability); GPT-5.6 Sol takes spec planning, C+ to F (68% vs 21% capability); GPT-5.6 Sol takes vibe coding, D+ to F (51% vs 22% capability). Claude Haiku 4.5 used 1% of Claude Max 5x's weekly limit per pass, $0.012 per task at the listed price. GPT-5.6 Sol used 3% of ChatGPT Pro 5x's weekly limit per pass, $0.036 per task at the listed price. Per task, Claude Haiku 4.5 is about 3.0x cheaper ($0.012 vs $0.036). Claude Haiku 4.5 is faster on real-world issues: a median task takes 3m 8s against 3m 13s. Both finished every task on it. Reasons to pick Claude Haiku 4.5 anyway: it is cheaper per task ($0.012 vs $0.036) and it is faster on real-world issues (3m 8s vs 3m 13s median).
Changed since the previous graded week: Claude Haiku 4.5: real-world issues D+ to D-; GPT-5.6 Sol: vibe coding C- to D+.
| Dimension | Claude Haiku 4.5 | GPT-5.6 Sol | Advantage |
|---|---|---|---|
| Capability | 37% | 60% | +23% (GPT-5.6 Sol leads) |
| Median task time | 3m 8s | 3m 13s | 5s faster (Claude Haiku 4.5 leads) |
| Approx. task cost | $0.015 / task | $0.031 / task | $0.015 / task lower (Claude Haiku 4.5 leads) |
Claude Haiku 4.5: 8.0% of Claude Max 5x (8.0% / 5h, 1.0% / 1w) per run. Its weekly limit holds about 13.8 of the week's 33.6 5h windows. GPT-5.6 Sol: 2.0% of ChatGPT Pro 5x (2.0% / 1w) per run. Each figure is a share of that agent's own plan, so there is no delta to draw.
| Dimension | Claude Haiku 4.5 | GPT-5.6 Sol | Advantage |
|---|---|---|---|
| Capability | 21% | 68% | +47% (GPT-5.6 Sol leads) |
| Median task time | 2m 8s | 6m 0s | 3m 51s faster (Claude Haiku 4.5 leads) |
| Approx. task cost | $0.002 / task | $0.057 / task | $0.056 / task lower (Claude Haiku 4.5 leads) |
Claude Haiku 4.5: 1.0% of Claude Max 5x (1.0% / 5h) per run. Its weekly limit holds about 13.8 of the week's 33.6 5h windows. GPT-5.6 Sol: 1.0% of ChatGPT Pro 5x (1.0% / 1w) per run. Each figure is a share of that agent's own plan, so there is no delta to draw.
| Dimension | Claude Haiku 4.5 | GPT-5.6 Sol | Advantage |
|---|---|---|---|
| Capability | 22% | 51% | +29% (GPT-5.6 Sol leads) |
| Median task time | 4m 4s | 3m 56s | 7s faster (GPT-5.6 Sol leads) |
| Approx. task cost | $0.009 / task | $0.092 / task | $0.083 / task lower (Claude Haiku 4.5 leads) |
Claude Haiku 4.5: 1.3% of Claude Max 5x (1.3% / 5h) per good solve. Its weekly limit holds about 13.8 of the week's 33.6 5h windows. GPT-5.6 Sol: 0.4% of ChatGPT Pro 5x (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, Claude Haiku 4.5 or GPT-5.6 Sol?
GPT-5.6 Sol clears higher: tier 4 of 5 versus tier 2 for Claude Haiku 4.5 on real-world@v3, our private suite of real-world coding problems. Latest measurement 2026-09-28.
Which is cheaper per task, Claude Haiku 4.5 or GPT-5.6 Sol?
Claude Haiku 4.5 used 1% of Claude Max 5x's weekly limit per pass, $0.012 per task at the listed price. GPT-5.6 Sol used 3% of ChatGPT Pro 5x's weekly limit per pass, $0.036 per task at the listed price. Per task, Claude Haiku 4.5 is about 3.0x cheaper ($0.012 vs $0.036).
What do Claude Haiku 4.5 and GPT-5.6 Sol cost a month?
Claude Haiku 4.5 runs on Claude Max 5x at $100/month (public price as of 2026-07-20). GPT-5.6 Sol runs on ChatGPT Pro 5x at $100/month (public price as of 2026-09-05).