Google AI Ultra with Antigravity — How It Differs from Pro and Where It Helps Solo Developers

Google AI Ultra vs. Pro: What Actually Changes for Antigravity Users

In early 2026, Google introduced Google AI Ultra ($49.99/month) as a step up from the existing Google AI Pro ($19.99/month). For individual developers and small teams, the decision to upgrade comes down to one central question: how deeply are you relying on Antigravity's Max mode?

Here's a practical side-by-side comparison of the two plans:

Google AI Pro ($19.99/month):

• Access to Gemini 3.1 Pro model
• Google One 2 TB storage
• NotebookLM Plus (100 sources, 500 notebooks)
• Jules AI code assistant access
• Antigravity Max mode: 100 sessions/month

Google AI Ultra ($49.99/month):

• Access to Gemini 3.1 Ultra model (substantially stronger reasoning)
• Google One 30 TB storage
• NotebookLM Plus (no limits)
• Jules priority queue (up to 80% shorter wait times)
• Antigravity Max mode: unlimited
• Advanced Google Meet AI features
• Deep Research extended mode (3× deeper analysis)

The headline feature for Antigravity users is clear: unlimited Max mode. Pro plan users hitting the 100-session monthly cap — especially near the end of the month — know the frustration of switching to Fast mode just when you're deep in a complex refactoring task. Ultra eliminates that ceiling entirely. Beyond the session cap, the move from Gemini 3.1 Pro to Gemini 3.1 Ultra also brings noticeably better performance on ambiguous or architecturally complex prompts, where the Pro model sometimes produces correct-but-fragile code that needs a second pass to clean up.

What Antigravity Max Mode Actually Unlocks

Antigravity offers two primary operating modes. Fast mode handles quick completions, inline edits, and straightforward refactors efficiently. Max mode (also called Planning mode) brings in Gemini 3.1 Ultra for tasks that demand deeper reasoning:

• System-wide architectural decisions: Antigravity analyzes the entire dependency graph before suggesting structural changes
• Large-scale refactoring: Changes spanning dozens of files maintain consistency throughout
• Deep codebase analysis: Repositories with tens of thousands of lines become fully navigable
• Root cause debugging: The AI traces back through stack traces to identify the actual source of issues, not just symptoms

With Google AI Ultra, every Max mode session draws on Gemini 3.1 Ultra without counting toward a cap. For developers doing serious work — building products, maintaining multiple repositories, or running complex AI agent workflows — this shift is meaningful.

Step-by-Step Setup: Connecting Ultra to Your Antigravity Workflow

Step 1: Upgrade to Google AI Ultra

1. Visit Google One and check your current plan
2. Select the "Google AI Ultra" plan and complete payment (annual billing saves ~20%)
3. Restart Antigravity after the upgrade completes

Step 2: Verify the Plan Inside Antigravity

Confirm that Antigravity has picked up the upgrade.

# Open Command Palette → "Antigravity: Account Status"
# Or: Settings → Account → Plan should show "Google AI Ultra"
# You'll also see an "Ultra" badge in the bottom-right status bar

If the badge doesn't appear, clear Antigravity's authentication cache via the Command Palette and re-authenticate.

Step 3: Configure ANTIGRAVITY.md to Default to Max Mode

Add an ANTIGRAVITY.md file to your project root to tell Antigravity when to automatically prefer Max mode over Fast mode:

# ANTIGRAVITY.md
 
## Mode Defaults
- Use Planning (Max) mode for tasks involving multiple files
- Use Fast mode for single-file edits and quick completions
 
## Project Context
- Stack: Next.js 16 + Cloudflare Workers + TypeScript
- Testing: Vitest
- Deploy target: Cloudflare Pages
 
## Agent Rules
- Always list affected files before executing schema changes
- Run type-check after any interface modification

This configuration means you'll naturally land in Max mode for the work that warrants it — without having to remember to switch manually every session.

Step 4: Pair Jules Priority Queue with Antigravity

Ultra subscribers get Jules on a priority queue, which cuts average review wait times substantially. Here's a configuration pattern that lets Jules work in parallel with your Antigravity coding sessions:

// .jules/config.ts
export const julesConfig = {
  // Automatically request review on every PR
  autoReview: true,
  // Generate tests alongside new code
  autoGenerateTests: true,
  // Run linting on save
  lintOnSave: true,
  // Enable priority queue (Ultra plan only)
  priorityQueue: true,
};

The practical result: while you're writing a new feature in Antigravity, Jules is simultaneously generating tests and producing review comments. You finish coding and the review is already waiting — rather than sitting in a queue.

Is Ultra Worth the Cost? A Practical Breakdown

The math on upgrading:

Additional monthly cost: $49.99 − $19.99 = +$30/month (or ~$24/month on annual billing)

What that buys:

• Unlimited Max mode sessions (Pro cap: 100/month; cost to cover overages via Gemini API directly: ~$0.30–$0.50 each)
• Jules priority queue: roughly 30 minutes saved per PR review cycle
• Deep Research extended mode: estimated 2–3 hours/week saved on technical research
• NotebookLM without limits: critical for large documentation-heavy projects

If you're consistently hitting Antigravity's Max mode cap, the arithmetic often favors Ultra over paying for Gemini API access to compensate. Run the numbers for your own usage: Antigravity's settings panel shows your historical Max mode session count.

Common Issues and Fixes

Issue 1: Max mode still shows "100 sessions/month" after upgrading

Antigravity may have cached the old plan data. Open the Command Palette and run "Antigravity: Clear Authentication Cache," then sign in again. If that doesn't work, fully quit and relaunch Antigravity, then re-sync via Settings → Account.

Issue 2: Jules priority queue isn't activating

Jules uses its own authentication flow separate from Antigravity. Go to Settings → Integrations → Jules → Re-authenticate and reconnect your Google account. Verify the account you're using matches the one on your Ultra subscription.

Issue 3: Deep Research results look the same as Pro

Deep Research extended mode works best when paired with Antigravity's Web Search Agent in Max mode. Add web_search: enabled to your ANTIGRAVITY.md and confirm you're launching the task in Max (not Fast) mode. Note that Deep Research extended results can take 2–3 minutes to generate — this is expected behavior, not a hang. If the request times out, try breaking the research query into smaller, more specific sub-questions.

Looking back

One underappreciated aspect of the Ultra upgrade: because Gemini 3.1 Ultra handles longer contexts more gracefully than Pro, you'll also notice fewer "context window exceeded" errors during extended Antigravity sessions on large codebases. For teams working on monorepos or projects with many interconnected modules, this alone can justify the cost.

Google AI Ultra's most meaningful upgrade for Antigravity users is simply removing the Max mode session cap. If you're doing serious development work in Antigravity every day, that ceiling shows up as a real constraint — not just a theoretical one.

The $30/month increase over Pro is substantial for an individual developer, so it's worth measuring your actual Max mode usage before committing. Check your historical session count in Antigravity's account settings, and if you're regularly close to or over 100 per month, Ultra almost certainly pays for itself.

If you're new to the Google AI ecosystem and want to get the most out of Pro before considering Ultra, the Google AI Pro × Antigravity combination guide is the right starting point. Build the workflow there first, then layer in Ultra when you've hit the limits.

For a deeper look at structuring your full AI development portfolio across tools, AI IDE Portfolio & Workflow Optimization: The Complete Guide covers exactly that.