Claude 5.5 vs Claude Haiku 4.5
Wins 4 of 5 areas
Coding · Agents · Reasoning · Long documents
Wins 0 of 5 areas
—
Claude 5.5 is the stronger all-rounder.Claude Haiku 4.5 is cheaper.
Scores updated · 10 tests both models report · How we compare
Where each one wins
Tests won in each of the five areas where both have results. Each piece is one test, so a longer bar means more evidence; grey means the two scored within a point of each other.
- AgentsCarrying out multi-step tasks on its own20Claude 5.52 of 2 tests
- ReasoningHard problems that need careful thinking20Claude 5.52 of 2 tests
- CodingWriting and fixing software10Claude 5.51 of 1 test
- Long documentsFinding answers in very long texts10Claude 5.51 of 1 test
- FactsGetting facts right instead of making them up11Even1 each
Coding and long documents rest on a single test each.
What it costs
Prices per million tokens, roughly 750,000 words. The bars show the cost of a million tokens read plus a million written.
Claude Haiku 4.5 costs 50% less for the same work.
The biggest differences
The tests each model wins by the widest margin, up to three each. Scores are out of 100.
Where Claude 5.5 pulls ahead
- Real work tasks from 44 professionsGDPVal+29.4points ahead
- Very hard expert questions across many subjectsHumanity's Last Exam+29.4points ahead
- Answers hard knowledge questions correctlyAA-Omniscience · Accuracy+29.2points ahead
Where Claude Haiku 4.5 pulls ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+23.9points ahead
Every test, side by side
All 10 tests both models report. The winning score is in its model's colour; marks a score checked independently.
AgentsClaude 5.5
- Terminal-Bench 4.0Claude 5.5 by 29.829.80+29.8
- GDPValClaude 5.5 by 29.441.211.8+29.4
ReasoningClaude 5.5
- Humanity's Last ExamClaude 5.5 by 29.439.810.4+29.4
- CritPtClaude 5.5 by 16.916.90+16.9
FactsEven
- AA-Omniscience · AccuracyClaude 5.5 by 29.247.218+29.2
- AA-Omniscience · Non-hallucinationClaude Haiku 4.5 by 23.948.872.7+23.9
Other results2 tests, not counted
Tests outside the eight areas. They are not counted above: several are summary scores built from other tests, or the same test under another name.
- AA-OmniscienceClaude 5.5 by 24.520.1-4.4+24.5
- AA IntelligenceClaude 5.5 by 23.940.816.9+23.9
Questions people ask
Which is better, Claude 5.5 or Claude Haiku 4.5?
Claude 5.5 wins four of the five areas where both have results: coding, agents, reasoning and long documents. Claude Haiku 4.5 wins none, but costs 50% less. They are level on facts.
Which is better for coding?
Claude 5.5. It wins the one coding test both models report.
Which is cheaper?
Claude 5.5 costs $2.00 per million input tokens and $10.00 per million output tokens; Claude Haiku 4.5 costs $1.00 and $5.00. That makes Claude Haiku 4.5 about 50% cheaper for the same work.
How do you compare the two?
We use the 10 benchmark tests both models have published scores on. The verdict counts the 8 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 2 are listed but not counted, because several are summary scores or repeat a test. Each score is the one shown on the model's own page.