Free Frontier Stack 2026

If you’re still paying for three different AI subscriptions just to get decent code completion, you’re doing it wrong. The model wars have shifted: frontier-level performance is now available without monthly fees—if you know where to look.

What this is: Working configurations for three distinct user tiers as of February 1, 2026. Not “free trials that convert automatically.” Not marketing bait. Actual free access to models that cost $200/month elsewhere.

The headline: You can get Claude Opus 4.5 (80.9% SWE-bench) completely free via Antigravity or AMP Ad-Supported—the $200/month model that beats everything else on reasoning. Or get Kimi k2.5 (76.8% SWE-bench, ~95% of Opus performance) free through multiple paths. Your choice depends on whether you need that final 4% of reasoning power or can work with near-frontier performance.

Already paying for AI? See how to optimize your spend → Smart Spend Guide

🟢 Free Tier: Max Out All Free Trials (No Credit Card Required)

The free tier in February 2026 is absurdly generous. You can get $500+ worth of compute without spending a dollar. Here’s how to extract maximum value from every free trial available.

Strategy: Stack these tools in order—each one gives you different models, different limits, and different use cases. By combining them all, you get frontier-level AI coding for weeks without paying.

These tools give you Sonnet 4.5-level performance (76.8% SWE-bench, comparable to Sonnet 4.5’s ~77%) without paying. You won’t get Opus 4.5 here, but you’ll get 95% of the capability at 0% of the cost.

1) OpenCode Zen: The Sustainable Daily Driver

What it is: Open-source AI coding client (72k+ GitHub stars) with hosted free tier.

Critical distinction: OpenCode Zen offers free Kimi k2.5 and GLM 4.7, but NOT Claude Opus 4.5. OpenCode does support Opus 4.5 in self-hosted mode with your own API keys (paid), but the free Zen tier doesn’t include it. For free Opus 4.5 access, see Antigravity or Kiro below.

Available models:

• Kimi k2.5 - 76.8% SWE-bench, Sonnet 4.5-competitive, native vision capabilities
• GLM 4.7 - 73.8% SWE-bench, chain-of-thought reasoning, 200K context

Best for: Daily coding work when you want sustained free access without API setup. Kimi k2.5’s vision-to-code capabilities (mockups → working UI) are unmatched in the free tier.

The value: You’re getting Sonnet 4.5-competitive coding (76.8% vs ~77%) plus superior multimodal capabilities at $0. Even if you later pay for Kimi API, it costs $3/1M tokens vs Claude Opus 4.5’s $25/1M (8x cheaper).

How to claim:

1. Visit opencode.ai or install via npm install -g opencode
2. Select “Zen” hosted option during setup
3. Create account (no credit card required)
4. Choose your model: Kimi k2.5 or GLM 4.7

The catch: Rate limits apply—OpenCode uses a pay-as-you-go model with spending limits, not request-based limits. Exact numbers are not published. Data used for training. Terms may change as the service matures.

Last verified: January 30, 2026

Tool deep dive: /tools/opencode/ - Self-hosted vs Zen comparison

2) Antigravity: Free Opus 4.5 (Best Free Reasoning)

ACTIVE

What it is: Google’s AI-native IDE (released November 18, 2025) in public preview.

Critical distinction: Antigravity offers free Claude Opus 4.5 access—yes, the $200/month model. Available alongside Gemini 3 Pro and Gemini 3 Flash. No credit card required.

Available models (verified Feb 1, 2026):

• Claude Opus 4.5 (Thinking) - 80.9% SWE-bench
• Claude Sonnet 4.5 - Fast, capable mid-tier model
• Gemini 3 Pro - Google’s flagship model
• Gemini 3 Flash - Speed-optimized with 1M context

Best for: Complex software architecture, debugging, and reasoning-heavy tasks. The agent workflow lets AI work autonomously while you review.

The value: Access to Opus 4.5 without the $200/month Claude Max subscription. The agentic workflow (AI edits, tests, iterates autonomously) is unique among free options.

Usage limits: Session-based limits apply (Opus 4.5 → Pro → Flash hierarchy). Plan accordingly for heavy sessions.

How to claim:

1. Visit antigravity.dev
2. Sign in with Google account (no credit card required)
3. Select your model from the dropdown
4. Start coding

The catch: Public preview means terms can change. Data handling terms differ from Anthropic’s direct service.

Tool deep dive: /tools/antigravity/

3) Kilo Code: BYOK Only (Free Kimi Removed Feb 3)

DEPRECATED

What it is: VS Code extension that previously offered free Kimi k2.5, now BYOK-only for Kimi.

Status Update (Feb 3, 2026):

• ❌ Free Kimi k2.5 removed from hosted tier
• ✅ BYOK mode still active — bring your own Moonshot API keys
• ✅ Other models may still have free tier offers

Current options:

• BYOK mode — Use your own API keys for Claude, GPT, Gemini, or Kimi k2.5
• Kilo Pass — Paid subscriptions from $19/month with bonus credits

The value: Still useful for VS Code users wanting IDE-native AI with BYOK flexibility, but no longer a free Kimi path.

For free Kimi k2.5 alternatives:

1. OpenCode Zen — Now the only ongoing free option
2. Kimi Code haggling — $0.99-$11.99 first month via AI agent
3. Kimi Code trial — 7-day free trial (card required)

Tool deep dive: /tools/kilo-code/ - VS Code integration, BYOK setup, current pricing

See also: Why free tiers are shrinking — strategic context

4) Kiro: 500 Credits/Month (Generous but No Opus 4.5)

500 CREDITS

What it is: CLI-first AI coding tool with generous free tier.

Critical distinction: Kiro gives you exactly 500 bonus credits for the first month—but Claude Opus 4.5 is NOT available on free tier (paid-only as of Jan 2026). You get Sonnet 4.5, Haiku 4.5, and Sonnet 4.0. That’s roughly 125-250 complex coding requests. After the first month, you keep getting 50 credits/month ongoing.

Free tier models: Auto, Sonnet 4.5, Haiku 4.5, Sonnet 4.0

Best for: One month of intensive usage on capable models. System design, complex debugging, and reasoning-heavy tasks. The CLI interface is perfect for terminal-centric workflows.

The value: 500 credits is generous, but since Opus 4.5 is excluded, this is less attractive than OpenCode Zen (free Kimi k2.5 ongoing) or Antigravity (free Opus 4.5). Consider this if you specifically want Sonnet 4.5 via CLI.

The Catch: Credit card required for signup. Credits expire after 30 days. Opus 4.5 requires paid tier.

How to claim:

1. Install Kiro CLI: npm install -g @kiro/cli (or download from kiro.dev)
2. Create new account during setup (credit card required)
3. Check credit balance with kiro credits—should show exactly 500 bonus credits
4. Use available models: kiro ask --model claude-4-5-sonnet "your prompt"

Sources: kiro.dev/pricing

Tool deep dive: /tools/kiro/ - CLI setup and credit optimization

5) AMP: Ad-Supported Daily Opus 4.5

DAILY REFRESH

What it is: Sourcegraph’s agentic coding tool with a free ad-supported tier featuring daily Opus 4.5 access.

Critical distinction: Unlike Antigravity (preview status uncertain) and Kiro (credits expire after 30 days), AMP’s ad-supported tier offers ongoing daily Opus 4.5 access with non-intrusive banner ads. No credit card, no expiration dates, predictable daily limits that refresh every 24 hours.

Available models:

• Claude Opus 4.5 - Daily allocation with ad-supported tier (resets every 24h)
• GPT-5.2 - General coding, fast iteration
• Claude Sonnet 4 - Balanced speed and capability
• Fast models - Simple edits, quick fixes

Best for: Developers who want sustainable, predictable Opus 4.5 access without worrying about preview terms changing or credits expiring. The ad experience is minimal (banner ads only).

The value: Ongoing access to the $200/month model. The trade-off is modest daily limits and non-intrusive ads—worth it for users who need consistent Opus 4.5 without expiration anxiety.

How to claim:

1. Visit ampcode.com
2. Select “Free Tier (Ad-Supported)”
3. Sign up (no credit card required)
4. Daily Opus 4.5 quota refreshes every 24 hours

Tool deep dive: /tools/amp/

6) Design & Prototyping (Bonus Tools)

While these don’t offer free AI coding tokens, they’re essential for frontend work and worth maxing out their free tiers:

Lovable (lovable.dev) - AI-powered full-stack app builder. Upload designs, get working React apps. Free tier includes project hosting and collaborative editing.

v0 (v0.dev) - Vercel’s UI generation tool. Describe components in natural language, get shadcn/ui React code. Free for personal projects with Vercel deployment.

Best for: Rapid prototyping, turning mockups into code, generating UI components without writing CSS. Use these alongside your free coding AI for complete workflows.

📊 Free Tier Summary: Total Compute Available

If you max out every free trial mentioned above, here’s what you get:

Total Value: $500+ worth of frontier AI compute without spending a dollar.

Strategy: Start with OpenCode Zen (best ongoing free Kimi k2.5), add Antigravity for Opus 4.5 tasks, use Kilo Code for VS Code integration with BYOK, and stack Kiro 500 credits + AMP daily quota for maximum free compute.

🟡 Value Tier: When Free Trials Run Out

Best value upgrades after exhausting free tiers:

Kimi Code (AI haggling) — Interact with “Kimmmmy” AI agent to unlock personalized pricing: $0.99 to $11.99 first month, then $19/month. See complete haggling guide for strategy.

z.ai ($30/year) — $2.50/month for GLM 4.7 with API access. Best for year-round sustainable access without managing multiple free trials. See full z.ai review for details.

Other options:

• Kimi k2.5 API — $3/1M tokens (pay-as-you-go)
• Claude Pro — $20/month for official Anthropic tooling

🔵 Paid Tier: $20+/Month Professional Tools

When you’re ready to pay but don’t want the $200/month Claude Max commitment.

Claude Code (Claude Pro: $20/month)

What it is: Anthropic’s official CLI coding tool.

Critical update: Claude Code is now available on the $20/month Claude Pro plan—previously required $200/month Max plan. This is significant value at the entry-level paid tier.

Best for: Professional developers who want official Anthropic tooling with guaranteed availability and enterprise compliance.

The value: Direct access to Claude models through official channels. No rate limit uncertainty. Enterprise-grade terms.

The catch: $20/month minimum. No free tier. Opus 4.5 usage may still have limits on Pro plan (verify current terms).

Where to learn more: Smart Spend Guide - When Claude Pro/Max makes sense

At a Glance: Choose Your Tier

Key Changes (Feb 2026): Kiro no longer includes Opus 4.5 on free tier (paid-only). Kilo Code removed free Kimi k2.5 (now BYOK-only). This makes OpenCode Zen the best overall free option for ongoing Kimi k2.5 access. For free Opus 4.5, use Antigravity or AMP.

When you exhaust free trials:

1. Kimi Code haggling — $0.99-$11.99 first month
2. z.ai $30/year — Best value for sustained usage ($2.50/mo)
3. Claude Pro — $20/month for official Anthropic tooling

Bottom line: Start with OpenCode Zen (best free). Stack other free trials for $500+ value. Only pay when you must.

Recommended Stack by Goal

“I want the best free AI coding stack”

Priority order (best to good):

1. OpenCode Zen — Best ongoing free option (Kimi k2.5, no credit card)
2. Antigravity — Best free reasoning (Opus 4.5, no credit card)
3. Kilo Code — Best for VS Code users (BYOK flexibility)
4. Kiro — 500 credits but no Opus 4.5 (consider after above)
5. AMP — Daily Opus 4.5 if you need it ongoing

Total: $500+ worth of compute, zero dollars spent.

“What’s the single best free option?”

→ OpenCode Zen — Free Kimi k2.5 (76.8% SWE-bench), ongoing, no credit card required

“I need the best reasoning model for free”

→ Antigravity — Free Opus 4.5 (80.9% SWE-bench), no credit card, no ads

“I want free AI in VS Code”

→ Kilo Code — BYOK mode lets you use free API tiers

“I need Opus 4.5 every day without expiration”

→ AMP Ad-Supported — Daily Opus 4.5 refresh, sustainable long-term

“What about Kiro’s 500 credits?”

→ Only if you specifically want Sonnet 4.5 via CLI. Note: Opus 4.5 is NOT included on free tier anymore.

The Upgrade Path

The smart progression:

1. Start with best free: OpenCode Zen (Kimi k2.5) + Antigravity (Opus 4.5) + Kilo Code (VS Code BYOK)
2. Stack additional free: Kiro 500 credits + AMP daily quota = $500+ total value
3. Value tier: Kimi Code haggling for $0.99-$11.99 first month, or z.ai at $30/year ($2.50/mo) for sustainable GLM 4.7 access
4. Professional: Claude Pro ($20/mo) for official Anthropic tooling
5. Maximum usage: Claude Max ($200/mo) only if you genuinely need unlimited Opus 4.5

Most developers: Start with OpenCode Zen (best free option). Add Antigravity for complex tasks. Use Kilo Code if you’re in VS Code. Only pay when you’ve exhausted $500+ of free compute.

Current Status & Verification

Last verified: February 3, 2026.

Related Resources

Value Section:

• Kimi Access Guide — $0.99 haggling, free tiers, tier selection
• Smart Spend Guide — When to upgrade from free to paid

Model Guides:

• Kimi k2.5 Model Guide - 76.8% SWE-bench, vision capabilities
• GLM 4.7 Model Guide - 73.8% SWE-bench, thinking mode
• Gemini 3 Flash Model Guide - 78% SWE-bench, FREE input tokens

Analysis:

• Kimi k2.5 Pricing Strategy — Why Moonshot’s pricing exists and where it’s heading
• Budget Model Comparison — Under $1/1M tokens compared

Verification & Risks:

• Kimi Terms Verification — Evidence levels for all pricing claims
• Kimi Data Risks — Data handling and compliance considerations

Tool Deep Dives:

• /tools/opencode/ — Best free option (Kimi k2.5, last standing)
• /tools/antigravity/ — Free Opus 4.5 from Google
• /tools/kilo-code/ — VS Code integration (BYOK only for Kimi as of Feb 3)
• /tools/kiro/ — 500 credits (but no free Opus 4.5)
• /tools/amp/ — Daily Opus 4.5 refresh
• /tools/zai/ — $30/year value tier (GLM 4.7)

Last updated: February 3, 2026. Deals verified via official sources. Promotional offers subject to change—always check official sites for current terms.