EDITORIAL PICK

Z.ai (ChatGLM)

FreemiumAI chatfreemium

Z.ai is Zhipu AI's chat and developer platform built on the GLM model family (formerly ChatGLM), and one of the fastest-moving labs of 2026. Basic chat on GLM Flash models is free and unlimited, while the flagship GLM-5.x reasoning models -- which rival Opus-class systems on agentic and coding tasks -- come via cheap coding-plan subscriptions (from ~$10/mo) or a very low-cost API. Developers get a strong, English, OpenAI-compatible platform with genuinely free Flash models, not just trial credits. The catch is China jurisdiction and PRC-aligned content rules, plus fast-shifting pricing.

Freemium · see pricing page
View Z.ai (ChatGLM)
VS

Microsoft Copilot

FreemiumAI chatconversational ai

Microsoft Copilot is ChatGPT-class AI baked into Windows 11, Edge, and Microsoft 365, running on GPT-5-era OpenAI models in 'Smart mode.' The free tier is unusually complete -- voice, Think Deeper reasoning, Deep Research, image generation, memory, and web search. The standalone 'Copilot Pro' was discontinued; paid Copilot now comes bundled into Microsoft 365 plans (Personal $9.99, Family $12.99, Premium $19.99). Its superpower is native OS and Office integration; its weakness is brand confusion and no dedicated consumer API.

Freemium · Family $12.99/mo, Premium $19.99/mo. No direct consumer API (build via Azure OpenAI). As of June 2026.
View Microsoft Copilot
EDITORIAL VERDICT · BIGBANGINDEX

Z.ai (ChatGLM) edges Microsoft Copilot on aggregate — 88 vs 81.

The best price-to-performance AI chat and API of 2026 -- free unlimited Flash chat and near-frontier paid models for cents, if your org is comfortable with a China-based provider. Microsoft Copilot still wins for buyers who prioritise generous free tier (voice, think deeper, deep research all free). Both tools are independently scored — the right pick depends on which dimensions matter most for your workflow.

SPEC SHEET

Side-by-side, every cell sourced.

Pricing pulled from each tool's public site. Scores follow the BigBang Score rubric — pricing transparency, free tier, API support, update frequency, unique factor, documentation, and community.

Feature
Z.ai (ChatGLM)
VS
Microsoft Copilot
Pricing model
Tier and access type
Freemium
vs
Freemium
Pricing detail
First-tier sticker
Free unlimited basic chat on GLM Flash models; flagship GLM-5.x via GLM Coding Plans (~$10/$30/$80/mo tiers). API: free Flash models plus cheap paid GLM-5.x (~$1-1.40/M input). Pricing shifting fast in 2026. As of June 2026.
vs
Free consumer tier at copilot.microsoft.com. Standalone Copilot Pro discontinued; paid Copilot is bundled in Microsoft 365: Personal $9.99/mo
Capabilities & access
Pricing transparency
How clear the pricing page is
15/20
vs
15/20
Free tier
Free plan generosity
14/15
vs
14/15
API support
Public API + SDK quality
14/15
vs
8/15
Update frequency
Shipping cadence
15/15
vs
13/15
Quality signals
Unique factor
Differentiation from peers
13/15
vs
14/15
Documentation
Docs depth + clarity
9/10
vs
8/10
Community
Active user community
8/10
vs
9/10
Verdict
BigBang Score
Composite of all 7 signals
88/100
vs
81/100
WHICH ONE FOR YOU?

Use-case picks.

Cut through the spec sheet. Here's what we'd recommend depending on what matters most.

Pick Z.ai (ChatGLM) if…

You prioritise unlimited free chat plus genuinely free api models and flagship glm-5.x rivals opus-class at a fraction of the cost.

ZPick: Z.ai (ChatGLM)

Pick Microsoft Copilot if…

You prioritise generous free tier (voice, think deeper, deep research all free) and native windows 11, edge, and office integration.

MPick: Microsoft Copilot

Editorial pick

Z.ai (ChatGLM) wins our composite score (88/100). It edges ahead on aggregate — but the right tool depends on which dimensions matter most.

ZPick: Z.ai (ChatGLM)
BigBangIndex Editorial
Independent AI tool reviews · Updated regularly

Each comparison uses the same 7-signal BigBang Score rubric. Pricing pulled from tool sites; capabilities verified against documentation. Affiliate links are disclosed inline and never affect rank.

FAQ

Z.ai (ChatGLM) vs Microsoft Copilot - frequently asked.

Direct answers tuned for AI search engines (ChatGPT, Perplexity, Claude) and Google's People Also Ask.

The short answer.

Z.ai (ChatGLM) wins on aggregate, but Microsoft Copilot pulls ahead on specific axes - the spec sheet above shows where each one earns its keep.