Abid niazi

Posted on May 18

I Built 56 Free Tools for Pakistani Students Using Next.js 14 — Architecture Deep Dive

#webdev #nextjs #javascript #typescript

Six months ago, I started building ToolForge — a free online toolkit with 56+ tools for students, developers, and professionals.

No ads. No signup. No data collection. Everything processes in the browser.

Here's the technical deep dive into how it's built.

The Stack

Next.js 14 App Router — server components for SEO, client components for interactivity
TypeScript — caught hundreds of bugs before deployment
Tailwind CSS — consistent dark theme across 56+ pages
Gemini AI — powers 4 AI tools via a custom key rotation system
Vercel — auto-deploy on push, free tier handles all traffic

Dual-URL Architecture

Every tool gets TWO indexable URLs:
/tools/calculators/emi-calculator ← the interactive tool
/emi-calculator ← long-form SEO guide page

The tool page targets action keywords ("emi calculator"). The guide page targets informational keywords ("how to calculate emi in pakistan"). This doubled our indexed pages without duplicating content.

The AI Challenge: Free Tier Key Rotation

We built 4 AI tools (Summarizer, Grammar Checker, Paraphraser, Essay Writer) using Google Gemini's free tier.

The problem? 15 requests/minute per key.

Our solution: round-robin rotation across 5 API keys with automatic failover on 429 errors.

// Simplified version of our key rotation
const keys = [KEY_1, KEY_2, KEY_3, KEY_4, KEY_5];
let currentIndex = 0;

async function fetchWithKeyRotation(prompt: string) {
  for (let attempts = 0; attempts < keys.length; attempts++) {
    try {
      const response = await fetch(GEMINI_URL, {
        headers: { 'x-goog-api-key': keys[currentIndex] }
      });
      if (response.status === 429) {
        currentIndex = (currentIndex + 1) % keys.length;
        continue;
      }
      return response.json();
    } catch (e) {
      currentIndex = (currentIndex + 1) % keys.length;
    }
  }
  throw new Error('All keys exhausted');
}

Result: 150,000 free API calls/month. Our AI tools are genuinely free to use.

Pakistan-Specific Tools

Instead of competing globally, we built tools nobody else has:

MDCAT Aggregate Calculator — medical college admission formula
NUST/FAST/UET Merit Calculators — university admission aggregates
FBR Income Tax Calculator — Pakistan tax slabs
Electricity Bill Calculator — NEPRA slab rates
Zakat Calculator — Islamic finance with PKR nisab values
University Comparator — compare aggregate across 5 universities at once

These tools have almost zero global competition but massive local demand.

SEO Results (3 Months)

Metric	Value
Indexed pages	86
Organic keywords	82 (+1,071%)
CTR	12.1% (industry avg: 2-5%)
Total tools	56
Guides/blogs	19

The high CTR tells us titles work. The average position (~23) tells us we need more backlinks. Hence this post.

Lessons Learned

Blogs drive more traffic than tools. Our pillar guides (25-30 min reads) rank better than individual tool pages.
Build for a niche first. Pakistan-specific tools have zero competition. We rank for keywords no one else targets.
Key rotation makes free tiers viable. Don't pay for APIs until you've exhausted free tier creatively.
Dual URLs per tool = 2x indexed pages. Simple architectural decision with massive SEO impact.

Try It

Everything is live and free at freetoolforge.org.

The AI Essay Writer and University Comparator are the most popular tools right now.

Happy to answer questions about the architecture in the comments.

Built by Abid Niazi — Full Stack Developer, Pakistan

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