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Side-by-side comparison · AI Assistants & LLMs

ChatGPT vs Google Gemini vs Z.ai

Everything that matters when choosing between them, in one place: our rating, what each can do, what they cost, and the trade-offs.

Best overall

ChatGPT

4.3

From $8/mo

Google Gemini

4.2

From US$4.99/mo

Z.ai

3.5

From $18/mo or $12.60/mo

Comparing 3 tools, the maximum.

At a glance

Best overallEasiest to use

Pick it if: Anyone who wants one general-purpose assistant that handles most everyday jobs.

Pick it if: People whose work already runs on Gmail, Google Workspace or an Android phone.

Z.ai3.5

Pick it if: Developers who want a cheaper engine for Claude Code and similar tools, and anyone who wants free access to a top open model.

Overview

AttributeChatGPTGoogle GeminiZ.ai
In one lineOpenAI's all-rounder: chat, images, voice, web search and agents in one app.Google's assistant, built into Gmail, Docs, Drive and Android phones.Free chat with Zhipu's open GLM models, plus a cheap coding plan for Claude Code users.
Pricing modelFreemiumFreemiumFreemium
Starting price$8/moUS$4.99/mo$18/mo or $12.60/mo
Free plan Yes Yes Yes
Works with Claude Code No No No

Rating breakdown

Our scores out of 5. The higher bar in each row is highlighted.

AttributeChatGPTGoogle GeminiZ.ai
Overall rating4.3Winner4.23.5
Ease of useHow quickly someone non-technical gets value from it.
4.5
4.0
3.5
FeaturesHow completely it covers its own job, and how well the pieces fit together.
5.0
4.5
3.5
Output qualityHow good the results are before you fix them.
4.0
4.0
4.0
Value for moneyWhat you get for the price, including the free plan.
4.0
4.0
3.5
Speed & reliabilityHow fast it is and how often it falls over.
4.0
4.5
3.0

Feature comparison

A tick means it does this today. A dash means we haven't checked.

AttributeChatGPTGoogle GeminiZ.ai
Access & platform
Free plan Yes Yes Yes
Mobile app Yes Yes No
Desktop app Yes Yes No
Browser extension Yes Yes No
API access Yes Yes Yes
Teams & business
Team workspace Yes Yes Yes
Enterprise plan or SSO Yes Yes No
Connects to other apps Yes Yes No
Open source or self-hosted No No Yes
AI abilities
Works with your files Yes Yes Yes
Understands images Yes Yes Yes
Makes images Yes Yes No
Makes video No Yes No
Writes code Yes Yes Yes
Runs agents or automations Yes Yes Yes
Learns your brand or style Yes Yes No
Works in many languages Yes Yes Yes
Capabilities score15/ 1716/ 179/ 17

Pricing

Plans as listed on each vendor's site when we last checked. Confirm before you buy.

AttributeChatGPTGoogle GeminiZ.ai
Plans

Free

Free

Trying it out and everyday questions.

Free

Free

Light use and seeing how it feels.

Chat

Free

Anyone who wants to try GLM or use Agent mode.

Go

$8/mo

Casual users who hit the free limits.

Google AI Plus

US$4.99/mo

Casual users who want Gemini in Gmail and more storage.

Coding Plan LiteOur pick

$18/mo or $12.60/mo billed yearly

Developers trying GLM inside their coding tool.

PlusOur pick

$20/mo

Anyone using it most days for work.

Google AI ProOur pick

US$19.99/mo

Anyone who works in Google Workspace every day.

Coding Plan Pro

$80/mo or $56/mo billed yearly

Daily agentic coding.

Pro

From $100/mo

Heavy users and people living in Codex.

Google AI Ultra

From US$99.99/mo

Heavy creative and agent users.

Coding Plan Max

$168/mo or $117.60/mo billed yearly

Developers running agents for hours every day.

Business

See website

Teams from 2 people up.

Which plan to pickThe free plan is now good enough to use properly, so stay on it until the image, voice or research limits annoy you. Plus is the sensible upgrade. Only look at Pro if you run Codex or deep research all day, and read the current tier details first: Pro 200 now comes with a smaller allowance than it did before 29 September.Skip the free plan for anything serious now that it's Flash-Lite only. AI Pro (US$19.99, or A$32.99 in Australia) is the one to buy: it's the cheapest way to get Gemini 4 Argon plus Gemini in Docs and Gmail, and the 5 TB of storage offsets a Google One bill. Ultra is for people generating video all day.For chat, it's free. Developers should start with Coding Plan Lite and code off-peak, because usage between 2pm and 6pm Singapore time on weekdays costs more credits. Move to Pro only if you hit the weekly cap.

Key features

AttributeChatGPTGoogle GeminiZ.ai
Standout features
  • Image generation and editing
  • Voice mode
  • Deep research
  • ChatGPT Work
  • Plugins and connectors
  • Codex and Sites
  • Gemini in Gmail, Docs and Drive
  • Deep Research
  • Image and video making
  • Gemini Live and desktop apps
  • Tasks and connected apps
  • Gemini in Chrome
  • Free chat
  • Agent mode
  • GLM Coding Plan
  • Open models
  • Vision coding

Pros and cons

AttributeChatGPTGoogle GeminiZ.ai
Pros
  • The widest set of built-in tools of any assistant
  • Free plan includes unlimited text chat with GPT-6 Luna
  • Image generation and voice mode are the best in the category
  • Huge ecosystem of plugins, connectors and guides
  • One subscription covers the Codex coding agent too
  • Reads and acts on your Gmail, Docs and Drive directly
  • AI Pro bundles the top model, Workspace features and 5 TB of storage for one price
  • Deep Research is included even on the free plan
  • Fast, and the mobile and Android experience is polished
  • Video and image generation included on paid plans
  • Desktop apps for Windows and Mac as well as the web
  • Free chat with a top open model and a capable Agent mode
  • Coding Plan plugs GLM into Claude Code, Codex and similar tools for less than top Claude plans
  • Open models under an MIT licence for most versions
  • GLM is strong at coding and long agent tasks
Cons
  • Writing sounds generic unless you work hard on the prompt
  • Plans and limits change often, and Pro now runs to $500 a month
  • Free and Go plans may show ads
  • It's confident when it's wrong, so check facts before you publish
  • Custom GPTs are being retired, so anything built on them needs moving to plugins
  • Free plan is now Flash-Lite only, so it's weaker than the free tiers of ChatGPT or Claude
  • Plan names and model access keep changing, which is confusing
  • Writing quality sits behind Claude and the answers can be padded
  • Workspace features need a personal Google account or a Workspace admin to turn them on
  • Usage resets every 5 hours up to a weekly cap, and Google doesn't publish the numbers
  • Slowdowns, rate limits and throttling at busy times, with a public apology from Zhipu in 2026
  • Prices and usage rules keep changing, including a 30% rise and a switch to credits
  • Zhipu is on the US trade blacklist and its hosted service filters sensitive topics
  • No international mobile app and a plainer chat experience than Qwen or Kimi
  • Users report locked accounts, slow support and dashboard token counts far higher than their tools show

Who each one is for

AttributeChatGPTGoogle GeminiZ.ai
Best for
  • Everyday questions and brainstorming
  • Making and editing images in the chat
  • Voice conversations on your phone
  • Quick research with web search
  • Searching and summarising your Gmail
  • Drafting in Google Docs
  • Image and video generation on paid plans
  • Hands-free help on Android
  • Cheaper agentic coding in Claude Code or OpenCode
  • Free chat with a top open model
  • Quick slides and websites from Agent mode
  • Developers who want open models
You'll find it used by
  • Marketers
  • Small business owners
  • Students
  • Developers
  • Google Workspace teams
  • Marketers
  • Small business owners
  • Android users
  • Developers
  • Indie hackers
  • Students
  • Open-model fans

Questions people ask

Which is better, ChatGPT, Google Gemini or Z.ai?

ChatGPT scores highest overall in our ratings (ChatGPT 4.3/5, Google Gemini 4.2/5 and Z.ai 3.5/5). ChatGPT is best for everyday questions and brainstorming and making and editing images in the chat. Google Gemini is best for searching and summarising your Gmail and drafting in Google Docs. Z.ai is best for cheaper agentic coding in Claude Code or OpenCode and free chat with a top open model.

Which is cheaper, ChatGPT, Google Gemini or Z.ai?

ChatGPT: There's a free plan, and paid plans start at $8/mo. Google Gemini: There's a free plan, and paid plans start at US$4.99/mo. Z.ai: There's a free plan, and paid plans start at $18/mo or $12.60/mo.

Which is easier to use, ChatGPT, Google Gemini or Z.ai?

ChatGPT rates highest for ease of use in our scores. Anyone who wants one general-purpose assistant that handles most everyday jobs.

How we compare

Ratings are our own, from using each tool, across ease of use, features, output quality, value for money, speed & reliability.

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