SSyncDev

AI model comparison

GPT-5.6 Terra vs Sonar Reasoning Pro

Compare recorded price, context, output limits, speed, latency, capabilities, and input/output support. Every missing value stays visible, and unsourced benchmarks are excluded.

This GPT-5.6 Terra vs Sonar Reasoning Pro comparison is designed for teams choosing between two production model records, not for declaring a universal winner. GPT-5.6 Terra by OpenAI currently records 1.1M context, 128K maximum output, $2.00 input per 1M tokens, $12.00 output per 1M tokens. Sonar Reasoning Pro by Perplexity records 128K context, 4.1K maximum output, $2.00 input per 1M tokens, $8.00 output per 1M tokens. The tables below separate documented capabilities, commercial limits, directory measurements, and source-linked benchmark evidence so you can see where the data is complete and where independent testing is still required.

Side-by-sideSpecs and pricing, compared

OpenAI

GPT-5.6 Terra

OpenAI's mid-tier GPT-5.6 reasoning model with a 1.05M token context window, function calling, and vision, priced between GPT-5.5 and GPT-5.5 Pro.

Context
1.1M
Max output
128K
Input / 1M
$2.00
Output / 1M
$12.00
Output speed
—

Accepts

  • Text input
  • Image input
  • PDF input

Produces

  • Text output
Full model profileVendor docs ↗
VS

Perplexity

Sonar Reasoning Pro

Web-grounded Sonar for multi-step research questions that need cited reasoning

Context
128K
Max output
4.1K
Input / 1M
$2.00
Output / 1M
$8.00
Output speed
—

Accepts

  • Text input
  • Image input

Produces

  • Text output
Full model profileVendor docs ↗

At a glance

Decision snapshot

This is a directional summary of the values recorded in this directory—not a universal quality verdict. Test the finalists on your own prompts before committing.

Where GPT-5.6 Terra leads in recorded data

  • Context capacity: 1.1M
  • Maximum output: 128K

Where Sonar Reasoning Pro leads in recorded data

  • Output price: $8.00

Context capacity

Higher listed limit

GPT-5.6 Terra:1.1M

Sonar Reasoning Pro:128K

GPT-5.6 Terra

Maximum output

Higher listed limit

GPT-5.6 Terra:128K

Sonar Reasoning Pro:4.1K

GPT-5.6 Terra

Input price

Lower recorded price

GPT-5.6 Terra:$2.00

Sonar Reasoning Pro:$2.00

Same recorded value

Output price

Lower recorded price

GPT-5.6 Terra:$12.00

Sonar Reasoning Pro:$8.00

Sonar Reasoning Pro

Output speed

Higher recorded throughput

GPT-5.6 Terra:—

Sonar Reasoning Pro:—

No complete comparison

Time to first token

Lower recorded latency

GPT-5.6 Terra:—

Sonar Reasoning Pro:—

No complete comparison

Intelligence Index

Higher directory index

GPT-5.6 Terra:—

Sonar Reasoning Pro:—

No complete comparison

Evidence

Verified shared benchmarks

A score appears only when both records include a verified source. It is not treated as a universal ranking.

These two models haven't been measured on the same benchmark yet, so there's nothing meaningful to chart. Comparing scores from different tests would tell you more about the tests than the models — the specs and pricing above are the better guide here.

Specifications

Pricing, limits and capabilities

SpecificationGPT-5.6 TerraSonar Reasoning Pro
ProviderOpenAIPerplexity
Model familygpt-terrasonar-reasoning
Accepted inputstext, image, pdftext, image
Produced outputstexttext
Context window1.1MRecorded lead128K
Max output128KRecorded lead4.1K
Intelligence Index——
Input price / 1M$2.00$2.00
Output price / 1M$12.00$8.00Recorded lead
Output speed——
Time to first token——
Reasoning modeDocumentedDocumented
Tool callingDocumentedNot documented
Image inputDocumentedDocumented
Audio inputNot documentedNot documented
Structured outputDocumentedNot documented
LicenseProprietaryProprietary
ReleasedJul 9, 2026Jan 1, 2024

Workload guidance

Which model should you choose?

GPT-5.6 Terra currently leads on larger context, larger maximum output. Sonar Reasoning Pro currently leads on lower recorded output price. Choose according to the constraints that matter to your workload, then run the same representative prompts against both models before making a production commitment. Neither the larger number nor the lower price is automatically the better choice: prompt quality, tool reliability, modality support, rate limits, data policy, and provider implementation can change the result. Use this page to build a shortlist, confirm current terms in the linked sources, and validate quality, latency, and cost with your own traffic.

Provenance

Sources and data limits

Prices and hosted performance can change. SyncDev records source references and clearly separates documented specifications from measured values; confirm commercial terms with the provider before deployment.

Questions people ask

It compares recorded context and output limits, token prices, output speed, time to first token, Intelligence Index, modality support, tool and structured-output capabilities, release information, and only source-linked benchmarks verified on both records. Missing information is labeled rather than inferred.

Compare a different pair

Choose any two approved model records and review them with the same evidence rules.

Open model comparison