GPT-5.2 vs Claude Opus 4.6 vs Gemini 3

This article compares the Big 3 platforms dominating the AI market as of February 2026: GPT-5.6 from OpenAI, Claude Opus 5 from Anthropic, and Gemini 3.1 Pro from Google — analyzing from the perspective Thai organizations need to know, including real Benchmarks, API pricing, PDPA data security, and suitable Use Cases.

Meet the Big 3 AI Platforms

1. OpenAI — ChatGPT / GPT-5.6 (Sol, Terra, Luna)

OpenAI sparked the global conversational-AI wave with ChatGPT back in late 2022. Its current main line is the GPT-5.6 family, released publicly on 9 July 2026, split into three tiers by capability and price: Sol, Terra and Luna.

• Models: Sol — the most capable tier, aimed at hard problems such as complex coding · Terra — the mid tier for high-volume business work like customer support, internal tools and document analysis · Luna — the economy tier for high-throughput workloads
• Context window: all three share 1.05M tokens with a 128,000-token maximum output
• Best for: general-purpose work at high quality, multimodal tasks (image, audio, video), and organisations already invested in the OpenAI ecosystem
• API pricing: Sol $5 / $30 · Terra $2 / $12 · Luna $0.20 / $1.20 per million tokens (input/output) — reflecting the price cut of 30 July 2026

2. Anthropic — Claude Fable 5 / Opus 5 / Sonnet 5

Anthropic was founded by former OpenAI researchers. The Claude family now spans several tiers: official documentation lists Claude Fable 5 (available 9 June 2026) as its most capable generally available model, while Claude Opus 5 (24 July 2026) is the recommended choice for agentic coding and enterprise work, and Claude Sonnet 5 (30 June 2026) is the default model on the Free and Pro plans.

• Models: Fable 5 (highest capability) · Opus 5 (recommended for coding and enterprise work) · Sonnet 5 (balance of quality and cost) · Haiku 4.5 (fast and economical) — plus Mythos 5, available only to approved customers for defensive cybersecurity work, with no self-serve sign-up
• Context window: 1M tokens for Fable 5, Opus 5 and Sonnet 5 with 128,000-token maximum output; Haiku 4.5 sits at 200,000 tokens
• Best for: writing and reviewing code, multi-step agentic work, long-document analysis such as contracts and regulations, and organisations that weight data governance heavily
• API pricing: Fable 5 $10 / $50 · Opus 5 $5 / $25 · Sonnet 5 $2 / $10 · Haiku 4.5 $1 / $5 per million tokens

3. Google — Gemini 3.7 Flash / Gemini 3.1 Pro

Google DeepMind has changed the most of the three since the start of the year. Gemini 3.1 Pro, the former flagship, was shut down on 9 March 2026, and Gemini 3.7 Flash has been deprecated. The newest model in the family is Gemini 3.7 Flash, released on 13 August 2026.

• Models: the stable Flash line covers Gemini 3.7 Flash, 3.6 Flash, 3.5 Flash, 3.5 Flash-Lite and 3.1 Flash-Lite. On the Pro side, the highest usable model is Gemini 3.1 Pro, which remains in Preview rather than general availability
• Context window: both 3.7 Flash and 3.1 Pro Preview accept 1,048,576 tokens with a 65,536-token maximum output, and take text, images, video, audio and PDF as input
• Best for: organisations already on Google Workspace, work spanning multiple media types, and high-volume workloads where cost control matters
• API pricing: Gemini 3.7 Flash and 3.6 Flash at $0.75 / $3.75 per million tokens (promotional rate through 31 December 2026) · Gemini 3.1 Pro Preview at $2 / $12 for prompts up to 200,000 tokens, rising to $4 / $18 beyond that

Comparison Table: ChatGPT vs Claude vs Gemini

Let's look at a clear visual comparison across every dimension organizations should consider:

Which Tasks Are They Best For? — Recommendations by Use Case (Aug 2026)

No single AI is "the best at everything." The right choice depends on your organization's work. Here are recommendations for common Use Cases:

Document Work / Report Summaries / Contract Review

Recommended: Claude Opus 5 / Sonnet 5

Reason: a 1M-token context window reads entire long documents in one pass, output runs up to 128,000 tokens for detailed responses, and Thai language support is strong — ideal for summarizing meeting reports, reviewing government contracts, and analyzing TORs.

Creative Work / Content Marketing / Social Media

Recommended: ChatGPT (GPT-5.6)

Reason: Best Multimodal capabilities — creates Captions, Blog Posts, and Email Campaigns in various tones, generates images instantly with DALL-E 3, has a GPTs Store with Marketing-specific templates, and 65% reduced Hallucination compared to previous versions.

Data Analytics / Google Sheets / BI

Recommended: Gemini 3.1 Pro / Flash

Reason: Connects directly to Google Workspace, 1M token Context reads massive data volumes, analyzes Google Sheets data to create formulas and charts, summarizes from Gmail and Google Drive natively, and Flash offers very affordable pricing ideal for batch processing.

Code Review / Software Development

Recommended: Claude Opus 5 (Coding #1) or GPT-5.6 Sol (ultra-fast)

Reason: Anthropic documentation lists Opus 5 as its recommended model for agentic coding, and it handles large codebases well, and Claude Code for terminal-based development. GPT-5.6 Sol runs at 1,000 tok/s, ideal for automated coding pipelines.

Searching for Latest Information / Research

Recommended: Gemini 3.1 Pro

Reason: Connects directly to Google Search with real-time data updates, a context window above 1M tokens aggregates information from many sources in a single pass.

Agentic Workflow / Automation

Recommended: Claude Opus 5

Reason: Agent Teams enable multiple models to collaborate, Adaptive Thinking adjusts analysis depth based on complexity, 128K token Output supports long multi-step tasks — ideal for DevOps, Document Processing Pipelines, or QA Automation.

Cautions for Organizations — PDPA and Data Security

Adopting AI in an organization isn't just about convenience — you must also consider data security and PDPA legislation. Here's what organizations need to consider:

1. Data That Must Never Be Sent to AI

• Customer/employee personal data — national ID numbers, salaries, health information
• Trade secrets — cost formulas, procurement pricing, business plans
• Confidential contracts/agreements — NDAs, client contracts
• Financial data — unpublished financial statements, bank account numbers

2. API vs Chat Interface — Which Is Safer?

For organizations, using the API is significantly safer than using the Chat Interface (web/app) because:

Issue	Chat Interface	API
Data Used to Train Models	May be used (must opt out)	Not used (all providers)
Data Retention	Stores conversation history	Not stored, or stored for 30 days
Data Control	Limited	Full control
Suitable for Organizations	Personal use / general tasks	Enterprise-level use

3. Guidelines for Safe AI Adoption in Organizations

• Define an AI Policy — clearly specify what data can and cannot be sent to AI
• Use API instead of Chat — for work involving organizational data, use APIs with a Data Processing Agreement (DPA)
• Use Enterprise Plans — OpenAI (ChatGPT Enterprise), Anthropic (Claude for Business), and Google (Gemini for Workspace) all offer plans guaranteeing data is not used for training
• Train employees — teach staff what should and shouldn't be sent to AI
• Verify Output — AI may generate inaccurate information (Hallucination); always have someone review before actual use

What About Saeree ERP? Can It Use AI?

As an ERP provider, we understand that many organizations are interested in using AI alongside their ERP systems — such as having AI analyze accounting data, summarize reports, or forecast sales.

In the meantime, organizations using Saeree ERP can use AI from various providers as supplementary tools, such as:

• Use Claude to summarize PDF reports exported from the ERP system
• Use ChatGPT to write customer follow-up emails
• Use Gemini to analyze data in Google Sheets exported from the system

Caution: Do not send confidential organizational data directly to AI. Use anonymized data or access AI through Enterprise Plans that guarantee data security.

Summary — How to Choose the Right AI for Your Organization (Aug 2026)

There is no definitive answer to "which AI platform is best." Everything depends on your organization's work and needs. Summary as of February 2026:

• For three tiers to match budget → GPT-5.6, whose Luna tier is the cheapest per token of the three
• For coding and multi-step agentic work → Claude Opus 5, the model Anthropic recommends for exactly this
• If you already run Google Workspace → Gemini, which integrates without adding a new system
• For the lowest API pricing → Gemini 3.7 Flash or Claude Haiku 4.5
• For maximum security → Claude (AI Safety leader) or ChatGPT Enterprise
• For Automation / Agent → Claude Opus 5 (Agent Teams + 128K output)

Most importantly — regardless of which AI platform you choose, your organization must have a clear AI Policy, define what data can and cannot be sent, use Enterprise Plans for work involving sensitive data, and train employees to understand both the benefits and risks of AI.

AI isn't here to replace people, but people who know how to use AI will replace those who don't. What matters is not just which platform you choose, but choosing to use it correctly, safely, and appropriately for your organization's context.

- Grand Linux Solution Team

References

• Anthropic — Claude models overview (tiers, context windows, pricing)
• Anthropic — Claude Opus 5 (24 Jul 2026)
• Anthropic — Claude Sonnet 5 (30 Jun 2026)
• Anthropic — Plans and pricing
• OpenAI — API pricing (GPT-5.6 Sol / Terra / Luna)
• Google — Gemini API models (status and context windows)
• Google — Gemini API pricing
• Google — Gemini model deprecations (Gemini 3 Pro shutdown)
• Personal Data Protection Committee, Thailand — PDPA B.E. 2562 (2019)

If your organization needs an ERP system ready for the AI era, you can schedule a Demo or contact our consulting team for further discussion.