Last verified

Claude Sonnet vs Claude Haiku — which Claude is enough for the job?

Same family, two different jobs. Claude Haiku is half the price ($1 / $5 vs $2 / $10 per 1M) and the fastest tier on Anthropic's own latency table. Claude Sonnet is clearly stronger on hard work — 85.2 vs 73.3 on SWE-bench Verified, with a 1M context against 200K. Choose Sonnet as the default for coding and multi-step reasoning; choose Haiku for high-volume classification, extraction, and routing.

§ 01 / VERDICT

Who wins, category by category.

Skip to decision tree →
Category Winner Margin
Agentic coding · SWE-bench Verified AClaude Sonnet Sonnet 85.2 vs Haiku 73.3 — a 12-point gap (llm-stats, Jul 2026)
Overall intelligence · AA Intelligence Index AClaude Sonnet Sonnet 53 vs Haiku 30 on the 9-eval composite (Artificial Analysis v4.1)
Raw speed · output tokens/s BClaude Haiku Anthropic rates Haiku "Fastest" and Sonnet "Fast"; AA measures ~100 vs ~75 tok/s
API price · per 1M tokens BClaude Haiku $1 / $5 vs $2 / $10 — Haiku is exactly half on both sides while intro pricing lasts
Real cost on prose · tokenizer-adjusted BClaude Haiku Sonnet 5 runs Anthropic's newer tokenizer, so the gap per 1M characters is nearer 2.7×
Context window · API model AClaude Sonnet 1M vs 200K tokens — five times the room for repos and long documents
Max output · per response AClaude Sonnet 128K vs 64K tokens; Sonnet also gets the 300K batch-output beta
Knowledge freshness · reliable cutoff AClaude Sonnet Sonnet 5 is reliable to Jan 2026; Haiku 4.5 stops at Feb 2025
Price stability · what happens Sep 1 BClaude Haiku Sonnet's $2 / $10 is introductory through Aug 31; Haiku has no announced change
Best overall ·Depends Sonnet is the default for real work, Haiku is the volume tier — most teams run both
CHOOSE A · CLAUDE SONNET

If the task needs reasoning, not just throughput.

  • Coding — 85.2 vs 73.3 on SWE-bench Verified, a 12-point gap on real repository tasks
  • Context — a 1M-token window against Haiku's 200K, five times the room for repos and long documents
  • Longer answers — 128K max output per response versus 64K, plus a 300K batch-output beta Haiku doesn't get
  • Fresher knowledge — reliable to Jan 2026 against Haiku's Feb 2025 cutoff
  • Adaptive thinking — Sonnet 5 scales its own reasoning effort per request instead of a fixed thinking switch
CHOOSE B · CLAUDE HAIKU

If the work is simple and there is a lot of it.

  • Half price — $1 / $5 per 1M against Sonnet's $2 / $10, and $0.50 / $2.50 on the Batch API
  • Fastest tier — Anthropic's own latency table rates Haiku 4.5 the fastest Claude; Artificial Analysis measures ~100 output tokens/s versus ~75
  • Cheaper prose — the older tokenizer means roughly 2.7× lower cost per 1M characters, not 2×
  • Cheaper cache — $0.10/M cache reads and $1.25/M five-minute writes, half of Sonnet's
  • Enough for the easy 80% — 73.3 on SWE-bench Verified covers boilerplate, extraction, classification, and routing
§ 02 / PRICING

What it actually costs.

Cost calculator →
Aspect Claude Sonnet Claude Haiku
API · inputper 1M tokens · from snapshot verified Jul 11 $2.00 $1.00 B wins
API · outputper 1M tokens · from snapshot verified Jul 11 $10.0 $5.00 B wins
Cached inputPrompt-cache read $/1M · from snapshot verified Jul 11 $0.20 $0.10 B wins
Effective API costBlended workload $/1M · from snapshot verified Jul 11 $1.36 $0.68 B wins
API context windowMax input tokens · from snapshot verified Jul 11 1M A wins 200K
Real cost / 1M charsTokenizer-adjusted prose — Sonnet 5 runs the newer, token-hungrier tokenizer est. verified Jul 11 $0.77 $0.29 B wins
Standard rate from Sep 1, 2026What the API bill looks like after the intro period verified Jul 27 $3 / $15 per 1M Sonnet 5's $2 / $10 is introductory pricing through Aug 31, 2026; Anthropic's pricing table already lists the September rates, batch included ($1.50 / $7.50) $1 / $5 per 1M No repricing announced for Haiku 4.5 — so the same-family gap widens from 2× to 3× on September 1 B wins
Consumer plan accessWhere each model shows up in Claude subscriptions verified Jul 27 The default model Sonnet is what the Claude apps hand you on Free, Pro ($17/mo billed annually, $20 monthly) and Max — you don't have to pick it A wins Selectable, every tier claude.com/pricing lists Haiku under Models and usage on Free, Pro, Max and Team seats; nobody buys a subscription for it — it earns its keep on the API
§ 03 / FEATURES

Feature-by-feature, side by side.

Download CSV →
Capability Claude Sonnet Claude Haiku
API context window 1M tokens 200K tokens
Max output per response 128K tokens 64K tokens
300K batch-output beta output-300k header
Positioning Balanced default Volume / low-latency tier
Comparative latency (vendor table) Fast Fastest
Measured output speed ~75 tokens/s ~100 tokens/s
Agentic coding (SWE-bench Verified) 85.2% 73.3%
Intelligence Index (AA v4.1) 53 30
Adaptive thinking
Extended thinking toggle ✗ (adaptive instead) thinking.type
Vision / image input
Prompt-cache read ✓ $0.20/M ✓ $0.10/M
5-minute cache write $2.50/M $1.25/M
Batch API (50% off) ✓ $1 / $5 ✓ $0.50 / $2.50
Tokenizer generation ~ Newer, ~35% more tokens ✓ Previous, leaner
Reliable knowledge cutoff Jan 2026 Feb 2025
Tool use / agents
MCP support ✓ Native ✓ Native
Cloud availability API, Bedrock, Vertex, Foundry API, Bedrock, Vertex, Foundry
Consumer app availability ✓ Default model ✓ Selectable
§ 04 / BENCHMARKS

The numbers, not the spin.

Agentic coding · SWE-bench Verified
Claude Sonnet
85.2%
Claude Haiku
73.3%
llm-stats.com leaderboard · % resolved · Claude Sonnet 5 vs Claude Haiku 4.5 · cross-checked on benchlm.ai · Jul 2026
Overall intelligence · AA Intelligence Index
Claude Sonnet
53.0%
Claude Haiku
30.0%
Artificial Analysis Intelligence Index v4.1 · 9-eval composite · Sonnet 5 (adaptive reasoning, max effort) vs Haiku 4.5 (reasoning) · Jul 2026
§ 05 / DEEP DIVE

What each does best.

Brand hubs →
A · ANTHROPIC

Claude Sonnet

The model the Claude apps hand you by default — strong enough for most production work, and cheap enough that few teams bother routing around it.

Strengths

  • Coding — 85.2 on SWE-bench Verified, twelve points clear of Haiku on real repository tasks
  • Reasoning — 53 on the Artificial Analysis Intelligence Index against Haiku's 30
  • Context — a full 1M-token window at standard pricing, five times Haiku's 200K
  • Output room — 128K tokens per response, and up to 300K through the Batch API beta
  • Recency — reliable knowledge through Jan 2026, a year fresher than Haiku

Weaknesses

  • Twice Haiku's token price today, and three times it once the introductory rate expires on Aug 31, 2026
  • The newer Anthropic tokenizer produces roughly a third more tokens for the same text (2.6 vs 3.5 characters per token on our calibration), so the real gap on prose is wider than the sticker gap
  • Slower per token — Artificial Analysis measures ~75 output tokens/s against Haiku's ~100
  • Overkill for classification, extraction, and routing, where the extra capability changes nothing

Best for

  • Coding agents working inside a real repository
  • Multi-step reasoning and tool-heavy workflows
  • Long documents, large diffs, and 200K+ token contexts
  • Anything where a wrong answer costs more than the tokens
B · ANTHROPIC

Claude Haiku

The volume tier — half the price, the fastest Claude, and good enough for the shallow, repetitive calls that make up most of an agent's traffic.

Strengths

  • Price — $1 / $5 per 1M, exactly half Sonnet's current rate and a third of it from September
  • Speed — Anthropic's own latency table puts Haiku 4.5 ahead of every other Claude
  • Tokenizer — the previous, leaner tokenizer means fewer billed tokens for the same text
  • Cache economics — $0.10/M reads and $1.25/M five-minute writes are half Sonnet's on both sides
  • Batch floor — $0.50 / $2.50 per 1M is the cheapest first-party Claude you can buy

Weaknesses

  • Twelve points behind Sonnet on SWE-bench Verified and 23 points behind on the intelligence index
  • 200K context and 64K max output — a fifth and a half of Sonnet's ceilings
  • Knowledge stops at Feb 2025, so it is the wrong model for anything recency-sensitive
  • No adaptive thinking; only the older fixed extended-thinking toggle
  • Excluded from the 300K batch-output beta

Best for

  • Classification, extraction, tagging, and routing at volume
  • Support-ticket triage and templated drafting
  • Sub-agent and tool-call steps inside a larger Sonnet-led pipeline
  • Batch jobs where latency and unit cost dominate
§ 06 / SCENARIOS

Picked by scenario.

More scenarios →
01

Classifying a million support emails a month

You need each message tagged by intent and urgency. The prompt is short, the output is a label, and the volume is relentless.

Reasoning: Nothing in this task rewards deeper reasoning — it rewards throughput and unit cost. Haiku is half the price per token, roughly 2.7× cheaper per 1M characters of real prose once the tokenizer difference is counted, and the fastest Claude on Anthropic's own latency table. Sonnet would produce the same labels for more money.

Picked
Claude Haiku
Runner-up: Sonnet only for the ambiguous messages a confidence threshold kicks out
02

Coding agent working inside a real repository

The agent reads files, edits code, runs tests, and iterates until the suite is green. Failed attempts cost tokens and your attention.

Reasoning: The 12-point SWE-bench Verified gap (85.2 vs 73.3) lands exactly here: Haiku retries on tasks Sonnet closes, and a retry costs more than the price difference. Sonnet's 1M context also holds far more of the repository at once. Haiku is a false economy on repo work.

Picked
Claude Sonnet
Runner-up: Haiku for the mechanical sub-steps — file summaries, commit messages, lint fixes
03

Support-ticket triage at 10,000 tickets a day

Each conversation is short and formulaic; you need a first-pass draft reply and a routing decision, with a human reviewing the edge cases.

Reasoning: Anthropic's own worked example puts a support conversation at roughly 3,700 tokens and prices 10,000 of them at about $37 on Haiku 4.5. The same volume on Sonnet costs twice that today and three times from September, for output a human reviewer will edit anyway. Run Haiku as the first pass and escalate whatever the confidence score flags.

Picked
Claude Haiku
Runner-up: Sonnet on the escalated tail
04

Reading a 400-page contract in one pass

You want cross-references resolved across the whole document, not a chunked summary stitched together from a retrieval index.

Reasoning: Haiku's 200K window cannot hold the document, so you would be back to chunking and losing the cross-references you came for. Sonnet's 1M window fits it whole at standard pricing, and 128K max output leaves room for a real clause-by-clause write-up. Context, not intelligence, decides this one.

Picked
Claude Sonnet
Runner-up: Haiku with retrieval if the document genuinely splits cleanly
05

Cost-capped agent with a per-step router

You run a fixed monthly API budget and your agent makes thousands of calls a day, most of them shallow tool-calls and formatting steps.

Reasoning: The biggest lever on this bill is not the model — it is the split. Routing the shallow majority to Haiku at $1 / $5 and reserving Sonnet for the steps that actually reason typically halves spend without moving output quality, because the cheap steps were never capability-bound. Haiku carries the volume here by design.

Picked
Claude Haiku
Runner-up: Sonnet as the reasoning step the router escalates to
06

Claude Pro subscriber deciding what to click

You pay $20/mo (or $17 billed annually) and the model picker offers Haiku alongside Sonnet and the Opus-class models.

Reasoning: On a subscription you are spending message allowance, not dollars per token, so Haiku's price advantage buys you nothing — and its Feb 2025 knowledge cutoff and 200K context make it the weaker choice for chat. Leave the default alone. Haiku is a model you buy on the API, not one you pick in the app.

Picked
Claude Sonnet
Runner-up: Haiku only if you are deliberately conserving allowance on trivial prompts

Frequently asked.

Common questions about this comparison, with sources where they matter.

Q · 01 Is Claude Sonnet or Haiku better? +
Sonnet is the stronger model by a clear margin — 85.2 vs 73.3 on SWE-bench Verified and 53 vs 30 on the Artificial Analysis Intelligence Index — with five times the context window and a knowledge cutoff a year fresher. Haiku wins on price and speed: half the token cost and the fastest latency tier Anthropic publishes. Treat Sonnet as the default for anything that reasons, and Haiku as the tier you route shallow, high-volume calls to.
Q · 02 Is Haiku really half the price of Sonnet? +
Today, yes on the sticker: $1 / $5 vs $2 / $10 per 1M tokens. Two things change that. First, Sonnet 5's $2 / $10 is introductory pricing through Aug 31, 2026 — Anthropic's pricing table already lists $3 / $15 from September 1, which turns the gap into 3×. Second, Sonnet 5 uses Anthropic's newer tokenizer, which produces roughly a third more tokens for the same text (2.6 vs 3.5 characters per token on our calibration), so on ordinary prose the real gap is closer to 2.7× even now. See the real-cost-per-1M-characters row above, and model your own mix in the LLM API cost calculator.
Q · 03 Is Haiku good enough for coding? +
For shallow, mechanical code work — commit messages, boilerplate, file summaries, lint-level fixes — yes: 73.3 on SWE-bench Verified is a real score. For an agent editing a live repository it is not, and the reason is economic rather than snobbery. A twelve-point resolve-rate gap means Haiku retries on tasks Sonnet closes, and each retry burns tokens and wall-clock time until the saving is gone. If coding is the workload, default to Sonnet and hand Haiku the mechanical steps.
Q · 04 How should I split traffic between them? +
Route by task shape, not by budget mood. Send classification, extraction, tagging, routing, and templated drafting to Haiku; send anything multi-step, repository-scale, or recency-sensitive to Sonnet. A confidence threshold or a schema-validation failure is a good automatic escalation trigger. Because both models share the same API surface and tool-use conventions, swapping the model id per request is usually a one-line change.
Q · 05 Which one is faster? +
Haiku. Anthropic's model table rates Haiku 4.5 the fastest Claude and Sonnet 5 one step below it, and Artificial Analysis measures roughly 100 output tokens/s for Haiku against 75 for Sonnet at max effort. The time-to-first-token difference is larger still, because Sonnet's adaptive thinking spends time reasoning before it emits anything. For interactive UI latency, Haiku is the noticeably snappier model.
Q · 06 Do they have the same context window? +
No. Sonnet 5 carries 1M input tokens and 128K max output; Haiku 4.5 carries 200K input and 64K output. Sonnet is also the only one of the two eligible for the 300K batch-output beta. If your prompts routinely exceed 200K tokens, the choice is already made for you — and note that Sonnet's newer tokenizer means its 1M window holds fewer characters per token than the raw number suggests.
Q · 07 Which model do I get on a Claude subscription? +
Sonnet is the model the Claude apps default to across Free, Pro ($17/mo billed annually, $20 monthly) and Max, and Anthropic's pricing page lists Haiku as selectable on every tier including Free and Team seats. In practice the subscription meters message allowance rather than tokens, so picking Haiku in the app saves you very little — Haiku earns its keep on the API. If you are weighing the plans themselves, see Claude Free vs Pro and Claude Pro vs Max.
Q · 08 Do they differ on privacy or non-English use? +
No. Both are Anthropic models under the same data-handling terms — API traffic is not used to train models by default — and both are multilingual with vision input. One caveat that is not a privacy issue but bites non-English users: token counts per character vary by language, and the two models run different tokenizer generations, so the cost ratio you measure on non-Latin scripts may differ from the 2× headline. Measure with your own text before committing.