Claude Sonnet 5 vs Composer 2.5
Claude Sonnet 5 is no longer on the leaderboard. 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 D overall. The two cost about the same per task. By suite, Composer 2.5 takes real-world issues (C- to D+) and spec planning is even at D. 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: Composer 2.5 vs Claude Sonnet 5
Both grade D overall. By suite: Composer 2.5 takes real-world issues, C- to D+ (57% vs 53% capability); spec planning is even at D (44% vs 48% capability); vibe coding is even at F (31% vs 23% capability). Claude Sonnet 5 used 2% of Claude Max 5x's weekly limit per pass, $0.024 per task at the listed price. Composer 2.5 used 2.0% of Cursor Pro's monthly limit per pass, $0.021 per task at the listed price. Per task the two cost about the same ($0.024 vs $0.021). Composer 2.5 is faster on real-world issues: a median task takes 1m 34s against 3m 35s. Both finished every task on it.
Changed since W39: Claude Sonnet 5: vibe coding D+ to F; Composer 2.5: real-world issues D+ to C-.
| Dimension | Claude Sonnet 5 | Composer 2.5 | Advantage |
|---|---|---|---|
| Capability | 53% | 57% | +3% (Composer 2.5 leads) |
| Median task time | 3m 35s | 1m 34s | 2m 1s faster (Composer 2.5 leads) |
| Approx. task cost | $0.015 / task | $0.021 / task | $0.006 / task lower (Claude Sonnet 5 leads) |
Claude Sonnet 5: 12.0% of Claude Max 5x (12.0% / 5h, 1.0% / 1w) per run. Its weekly limit holds about 13.8 of the week's 33.6 5h windows. Composer 2.5: 1.6% of Cursor Pro (1.6% / 1m) per run. Each figure is a share of that agent's own plan, so there is no delta to draw.
Work per window: Claude Sonnet 5 1218 vs Composer 2.5 63 suite runs per month (Claude Sonnet 5 leads); per plan-dollar: 12.18 vs 3.15 (Claude Sonnet 5 leads). Work figures compare outputs, so unlike quota shares they are comparable across plans.
| Dimension | Claude Sonnet 5 | Composer 2.5 | Advantage |
|---|---|---|---|
| Capability | 44% | 48% | +4% (Composer 2.5 leads) |
| Median task time | 5m 12s | 1m 8s | 4m 4s faster (Composer 2.5 leads) |
| Approx. task cost | $0.057 / task | $0.022 / task | $0.035 / task lower (Composer 2.5 leads) |
Claude Sonnet 5: 5.0% of Claude Max 5x (5.0% / 5h, 1.0% / 1w) per run. Its weekly limit holds about 13.8 of the week's 33.6 5h windows. Composer 2.5: 0.4% of Cursor Pro (0.4% / 1m) per run. Each figure is a share of that agent's own plan, so there is no delta to draw.
Work per window: Claude Sonnet 5 2922 vs Composer 2.5 225 suite runs per month (Claude Sonnet 5 leads); per plan-dollar: 29.22 vs 11.23 (Claude Sonnet 5 leads). Work figures compare outputs, so unlike quota shares they are comparable across plans.
| Dimension | Claude Sonnet 5 | Composer 2.5 | Advantage |
|---|---|---|---|
| Capability | 31% | 23% | +8% (Claude Sonnet 5 leads) |
| Median task time | 4m 31s | 1m 37s | 2m 54s faster (Composer 2.5 leads) |
| Approx. task cost | $0.007 / task | $0.022 / task | $0.015 / task lower (Claude Sonnet 5 leads) |
Claude Sonnet 5: 1.0% of Claude Max 5x (1.0% / 5h) per good solve. Its weekly limit holds about 13.8 of the week's 33.6 5h windows. Composer 2.5: 0.1% of Cursor Pro (0.1% / 1m) per good solve. Each figure is a share of that agent's own plan, so there is no delta to draw.
Work per window: Claude Sonnet 5 14610 vs Composer 2.5 920 good solves per month (Claude Sonnet 5 leads); per plan-dollar: 146.10 vs 46.02 (Claude Sonnet 5 leads). Work figures compare outputs, so unlike quota shares they are comparable across plans.
Grades and deltas are comparable only within a suite version. See methodology.
Frequently asked questions
Which is better for coding, Claude Sonnet 5 or Composer 2.5?
Claude Sonnet 5 clears higher: tier 3 of 5 versus tier 1 for Composer 2.5 on real-world@v3, our private suite of real-world coding problems. Latest measurement 2026-09-28.
Which is cheaper per task, Claude Sonnet 5 or Composer 2.5?
Claude Sonnet 5 used 2% of Claude Max 5x's weekly limit per pass, $0.024 per task at the listed price. Composer 2.5 used 2.0% of Cursor Pro's monthly limit per pass, $0.021 per task at the listed price. Per task the two cost about the same ($0.024 vs $0.021).
Which gives more coding work per dollar, Claude Sonnet 5 or Composer 2.5?
Claude Sonnet 5 delivers more benchmark work per subscription dollar: 12.18 suite runs per plan-dollar versus 3.15 for Composer 2.5 (at $100/month priced 2026-07-20, and $20/month priced 2026-07-20). Work figures compare outputs, so unlike raw quota shares they are comparable across plans.
What do Claude Sonnet 5 and Composer 2.5 cost a month?
Claude Sonnet 5 runs on Claude Max 5x at $100/month (public price as of 2026-07-20). Composer 2.5 runs on Cursor Pro at $20/month (public price as of 2026-07-20).