Experiment overview
I create two git-branches, from the same parent commit.
In git-branch A, I input the two turns of chat message into Agent mode Cursor + Claude-4-sonnet
In git-branch B, I input the same two turns of chat message into Claude Code
I compare the difference, the before/after in costs for git-branch A vs git-branch B to do the feature implemenation.
Start Time: 07-22-2025: 6:22pm KST
- Privacy Mode: Data Sharing Enabled
End Time: 07-22-2025:
Cursor current status:
@Start Time (07-22-2025: 6:22pm KST)
claude-4-sonnet-thinking:
- input (w/ cache write): 4,310,746
- input (w/o cache write): 537,388
- cache read: 26,186,758
- output: 376,728
- total tokens: 31,411,620
- API Cost: $31.79
Total:
- API Cost: $56.71
Cursor Experiment - Git Branch A (Request id: turn3: 7a2eadbb-4fd6-4a61-97de-a083b5ad6e30
, turn4: 1331f1b9-4d73-4fbb-bf6b-3a5bea861efd
)
Exact same prompt given to Cursor + Claude-4-sonnet and Claude Code
<INSTRUCTIONS_A>
ā Turn 1 cost: claude-4-sonnet-thinking Input (w/ Cache Write): 67,282, Input (w/o Cache Write): 45, Cache Read: 138,524, Output: 2,289, Included
2nd-turn
<INSTRUCTIONS_B>
ā Turn 2 cost: claude-4-sonnet-thinking Input (w/ Cache Write): 54,133, Input (w/o Cache Write): 6,578, Cache Read: 851,303, Output: 10,526, Included
@End time (6:47pm KST)
claude-4-sonnet-thinking:
- input (w/ cache write): 4,432,161
- input (w/o cache write): 544,011
- cache read: 27,176,585
- output: 389,543
- totak tokens: 32,542,300
- API Cost: $32.75
Total:
- API Cost: $57.67
Turn 1 & 2 cost in dollars: $57.67-$56.71 = $0.96
There is a bug, doing 3rd turn with Agent Cursor + Claude
3rd-turn
<INSTRUCTIONS_C>
ā Turn 3 cost: claude-4-sonnet-thinking Input (w/ Cache Write): 89,162, Input (w/o Cache Write): 181, Cache Read: 88,179, Output: 893, Included
Turn 3 @End time (6:47pm KST)
claude-4-sonnet-thinking:
- input (w/ cache write): 4,521,323
- input (w/o cache write): 544,192
- cache read: 27,264,764
- output: 390,436
- totak tokens: 32,720,715
- API Cost: $33.13
Total:
- API Cost: $58.05
Request id: 7a2eadbb-4fd6-4a61-97de-a083b5ad6e30
Turn 3 cost in dollars: $58.05-$57.67 = $0.38
Another bug. Must do 4-th turn
<INSTRUCTIONS_D>
ā Turn 4 cost: claude-4-sonnet-thinking Input (w/ Cache Write): 95,148, Input (w/o Cache Write): 265, Cache Read: 826,582, Output: 4,889, Included
Turn 4 @End time (6:59pm KST)
claude-4-sonnet-thinking:
- input (w/ cache write): 4,616,471
- input (w/o cache write): 544,457
- cache read: 28,091,346
- output: 395,325
- totak tokens: 33,647,599
- API Cost: $33.81
Total:
- API Cost: $58.73
Turn 4 cost in dollars: $58.73-$58.05 = $0.68
Cursor Git Branch A total cost: $58.73 - $56.71 = $2.02
Claude Code Experiment - Git Branch B
Claude Code API Key
@Start Time
API Key Cost: $18.05
@End Time
API Key Cost: $18.05
Exact same prompt given to Cursor + Claude-4-sonnet and Claude Code
<IDENTICAL_TO_CURSOR_EXPERIMENT_INSTRUCTIONS_A>
2nd-turn for additonal clarification
<IDENTICAL_TO_CURSOR_EXPERIMENT_INSTRUCTIONS_B>
@End Time
API Key Cost: $18.27
Turn 1+2 cost in dollars: $18.27-$18.05 = $0.22
There is a bug, doing 3rd turn with Agent Cursor + Claude
3rd-turn
<SMALL_CLARIFICATION_INSTRUCTION_C>
@End Time (7:18pm)
API Key Cost: $18.80
Turn 3 cost in dollars: $18.80 - $18.27 = $0.53
No need for turn 4 because Claude did the implementation successfully.
Claude Code Git Branch B total cost: $18.80 - $18.05 = $0.75
Conclusion
- Cursor Experiment - Git Branch A
- (Request id: turn3:
7a2eadbb-4fd6-4a61-97de-a083b5ad6e30
, turn4: 1331f1b9-4d73-4fbb-bf6b-3a5bea861efd
)
Total cost: $58.73 - $56.71 = $2.02
- Claude Experiment - Git Branch B
Total cost: $18.80 - $18.05 = $0.75
The same exact feature, with same chat instructons, same files attached in context to reach completion cost $2.02 in Cursor, and $0.75 with Claude Code in API Key.
Itās a 260 % difference.
In both case, I tested the code in the iOS simulator and it has nearly identical UI, and the same functionality.
@T1000
I hope this is sufficient. Iām almost at my account limit with Pro+ subscription and cannot do any more experiments for a while