Models

Every model we serve, with the numbers.

Claude and GPT models by their normal ids. Standard-tier models cost half the vendor list price; priority-tier variants are billed at a separate rate. Prices are USD per 1M tokens, excl. VAT, identical for API and chat.

Anthropic

9 standard-tier Anthropic models at half the list price.

Claude Fable 5.1NewPriority

claude-fable-5-1
−50%
Vendor
Anthropic
Context
200K
Max output
32K
  • Streaming
  • Tool calls
  • Vision
  • Reasoning
  • Structured outputs
  • Prompt caching
Halfbill price · priority routing
$7.50/ 1M in
list $15.00
$37.50/ 1M out
list $75.00
Specs and snippets

Claude Fable 5

claude-fable-5
−50%
Vendor
Anthropic
Context
200K
Max output
32K
  • Streaming
  • Tool calls
  • Vision
  • Reasoning
  • Structured outputs
  • Prompt caching
Halfbill price
$7.50/ 1M in
list $15.00
$37.50/ 1M out
list $75.00
Specs and snippets

Claude Opus 5

claude-opus-5
−50%
Vendor
Anthropic
Context
200K
Max output
32K
  • Streaming
  • Tool calls
  • Vision
  • Reasoning
  • Structured outputs
  • Prompt caching
Halfbill price
$3.75/ 1M in
list $7.50
$18.75/ 1M out
list $37.50
Specs and snippets

Claude Sonnet 5

claude-sonnet-5
−50%
Vendor
Anthropic
Context
200K
Max output
32K
  • Streaming
  • Tool calls
  • Vision
  • Structured outputs
  • Prompt caching
Halfbill price
$1.50/ 1M in
list $3.00
$7.50/ 1M out
list $15.00
Specs and snippets

Claude Opus 4.8

claude-opus-4-8
−50%
Vendor
Anthropic
Context
200K
Max output
32K
  • Streaming
  • Tool calls
  • Vision
  • Reasoning
  • Structured outputs
  • Prompt caching
Halfbill price
$3.75/ 1M in
list $7.50
$18.75/ 1M out
list $37.50
Specs and snippets

Claude Opus 4.7

claude-opus-4-7
−50%
Vendor
Anthropic
Context
200K
Max output
32K
  • Streaming
  • Tool calls
  • Vision
  • Reasoning
  • Structured outputs
  • Prompt caching
Halfbill price
$3.75/ 1M in
list $7.50
$18.75/ 1M out
list $37.50
Specs and snippets

Claude Opus 4.6

claude-opus-4-6
−50%
Vendor
Anthropic
Context
200K
Max output
32K
  • Streaming
  • Tool calls
  • Vision
  • Reasoning
  • Structured outputs
  • Prompt caching
Halfbill price
$3.75/ 1M in
list $7.50
$18.75/ 1M out
list $37.50
Specs and snippets

Claude Sonnet 4.6

claude-sonnet-4-6
−50%
Vendor
Anthropic
Context
200K
Max output
32K
  • Streaming
  • Tool calls
  • Vision
  • Structured outputs
  • Prompt caching
Halfbill price
$2.25/ 1M in
list $4.50
$11.25/ 1M out
list $22.50
Specs and snippets

Claude Haiku 4.5

claude-haiku-4-5
−50%
Vendor
Anthropic
Context
200K
Max output
32K
  • Streaming
  • Tool calls
  • Vision
  • Structured outputs
  • Prompt caching
Halfbill price
$0.75/ 1M in
list $1.50
$3.75/ 1M out
list $7.50
Specs and snippets

OpenAI

4 standard-tier OpenAI models at half the list price.

GPT-6 AstraNew

gpt-6-astra
−50%
Vendor
OpenAI
Context
400K
Max output
128K
  • Streaming
  • Tool calls
  • Reasoning
  • Structured outputs
  • Prompt caching
Halfbill price
$5.00/ 1M in
list $10.00
$25.00/ 1M out
list $50.00
Specs and snippets

GPT-5.6 Sol

gpt-5.6-sol
−50%
Vendor
OpenAI
Context
400K
Max output
128K
  • Streaming
  • Tool calls
  • Reasoning
  • Structured outputs
  • Prompt caching
Halfbill price
$2.50/ 1M in
list $5.00
$15.00/ 1M out
list $30.00
Specs and snippets

GPT-5.6 Terra

gpt-5.6-terra
−50%
Vendor
OpenAI
Context
400K
Max output
128K
  • Streaming
  • Tool calls
  • Reasoning
  • Structured outputs
  • Prompt caching
Halfbill price
$1.00/ 1M in
list $2.00
$6.00/ 1M out
list $12.00
Specs and snippets

GPT-5.5

gpt-5.5
−50%
Vendor
OpenAI
Context
400K
Max output
128K
  • Streaming
  • Tool calls
  • Reasoning
  • Structured outputs
  • Prompt caching
Halfbill price
$1.00/ 1M in
list $2.00
$8.00/ 1M out
list $16.00
Specs and snippets

Priority

Priority routing and higher cache efficiency for coding agents; billed at the priority rate.

Claude Fable 5 PriorityPriority

claude-fable-5-max
−40%
Vendor
Anthropic
Context
200K
Max output
32K
  • Streaming
  • Tool calls
  • Vision
  • Reasoning
  • Structured outputs
  • Prompt caching
Halfbill price · priority routing
$9.00/ 1M in
list $15.00
$45.00/ 1M out
list $75.00
Specs and snippets

Claude Opus 5 PriorityPriority

claude-opus-5-max
−40%
Vendor
Anthropic
Context
200K
Max output
32K
  • Streaming
  • Tool calls
  • Vision
  • Reasoning
  • Structured outputs
  • Prompt caching
Halfbill price · priority routing
$4.50/ 1M in
list $7.50
$22.50/ 1M out
list $37.50
Specs and snippets

Claude Sonnet 5 PriorityPriority

claude-sonnet-5-max
−40%
Vendor
Anthropic
Context
200K
Max output
32K
  • Streaming
  • Tool calls
  • Vision
  • Structured outputs
  • Prompt caching
Halfbill price · priority routing
$1.80/ 1M in
list $3.00
$9.00/ 1M out
list $15.00
Specs and snippets

Claude Opus 4.8 PriorityPriority

claude-opus-4-8-max
−40%
Vendor
Anthropic
Context
200K
Max output
32K
  • Streaming
  • Tool calls
  • Vision
  • Reasoning
  • Structured outputs
  • Prompt caching
Halfbill price · priority routing
$4.50/ 1M in
list $7.50
$22.50/ 1M out
list $37.50
Specs and snippets

Claude Opus 4.7 PriorityPriority

claude-opus-4-7-max
−40%
Vendor
Anthropic
Context
200K
Max output
32K
  • Streaming
  • Tool calls
  • Vision
  • Reasoning
  • Structured outputs
  • Prompt caching
Halfbill price · priority routing
$4.50/ 1M in
list $7.50
$22.50/ 1M out
list $37.50
Specs and snippets

Claude Opus 4.6 PriorityPriority

claude-opus-4-6-max
−40%
Vendor
Anthropic
Context
200K
Max output
32K
  • Streaming
  • Tool calls
  • Vision
  • Reasoning
  • Structured outputs
  • Prompt caching
Halfbill price · priority routing
$4.50/ 1M in
list $7.50
$22.50/ 1M out
list $37.50
Specs and snippets

Claude Sonnet 4.6 PriorityPriority

claude-sonnet-4-6-max
−40%
Vendor
Anthropic
Context
200K
Max output
32K
  • Streaming
  • Tool calls
  • Vision
  • Structured outputs
  • Prompt caching
Halfbill price · priority routing
$2.70/ 1M in
list $4.50
$13.50/ 1M out
list $22.50
Specs and snippets

Claude Haiku 4.5 PriorityPriority

claude-haiku-4-5-max
−40%
Vendor
Anthropic
Context
200K
Max output
32K
  • Streaming
  • Tool calls
  • Vision
  • Structured outputs
  • Prompt caching
Halfbill price · priority routing
$0.90/ 1M in
list $1.50
$4.50/ 1M out
list $7.50
Specs and snippets

Claude Haiku 4.5 20251001Priority

claude-haiku-4-5-20251001
−40%
Vendor
Anthropic
Context
200K
Max output
32K
  • Streaming
  • Tool calls
  • Vision
  • Structured outputs
  • Prompt caching
Halfbill price · priority routing
$0.90/ 1M in
list $1.50
$4.50/ 1M out
list $7.50
Specs and snippets

Endpoints and compatibility

All models are reachable through the OpenAI-compatible /v1/chat/completions and /v1/responses endpoints and through the Anthropic-compatible /v1/messages endpoint at https://api.halfbill.uk. Each model page shows both request shapes for that model id.

Halfbill is an independent service and is not affiliated with, endorsed by, or sponsored by OpenAI or Anthropic. Model names are trademarks of their respective owners.