The Consumer Money & Shopping Toolkit popup — 13 tools, one interface.
Consumer Money & Shopping Toolkit — Complete User Guide
13 tools · one license · all calculations explained
Version 1.0 · Updated 2026
The Consumer Money & Shopping Toolkit is the largest single bundle in the catalog, bringing together thirteen purpose-built tools for smarter shopping and money decisions. From shrinkflation tracking to fake-discount detection, warranty tracking, DeFi impermanent loss, and more — everything you need to make better financial decisions.
What Is the Consumer Money & Shopping Toolkit?
The Consumer Money & Shopping Toolkit is a Chrome extension that brings together 13 essential consumer tools into one unified interface. Every tool works with manual entry — no automatic data scraping — and stores all data locally in your browser.
This is the toolkit for savvy shoppers, consumers, and anyone who wants to make smarter money decisions — from tracking shrinkflation to detecting fake discounts, managing warranties, negotiating better deals, and even calculating DeFi impermanent loss.
Who Should Use This Toolkit?
- Shoppers & consumers — tracking product prices, sizes, and discounts over time.
- Budget-conscious buyers — finding the best deals and avoiding fake discounts.
- Warranty & return managers — tracking deadlines and expirations for purchases.
- Students & educators — finding free open-education alternatives to expensive textbooks.
- DeFi & crypto users — calculating impermanent loss and comparing gas costs across chains.
- Anyone who wants to save money — and make smarter financial decisions.
Why You Can Trust the Consumer Money & Shopping Toolkit
🔒 Trust built in Transparent logic, local data, and a proven track record.
Every calculation in this toolkit is documented and verifiable. All data stays local in your browser — no external servers, no data collection. The only network calls are optional Gumroad license verification and (if you choose) API calls to data providers using your own key.
Battle-tested logic
Impermanent Loss Calculator matches the standard reference values. Fake-Discount Verdict and Shrinkflation Tracker tested against real-world scenarios.
Documented calculations
Every formula is transparent and verifiable — no black-box algorithms.
100% local storage
All your data (shrinkflation logs, discount checks, warranty items, claim cases) stays in your browser.
No hidden data collection
Minimal permissions — only storage, alarms, and activeTab.
Why Use This Toolkit? (Key Benefits)
All 13 Tools — Detailed Guides
Each tool below includes its audience, formula (where applicable), key benefit, and a worked example.
1. Shrinkflation Tracker
Why use it? Log package size and price over time to see your real cost-per-unit change — catch shrinkflation before it hits your wallet.
Key benefit: See the true trend in your cost per unit, not just the package price.
formula Cost Per Unit = Price / Package Size
Product: "Granola Bars"
Jan 2026: Price $4.00, Size 16oz → Cost/unit: $0.25/oz
Jun 2026: Price $4.00, Size 12oz → Cost/unit: $0.33/oz
Percent Change: +33% (Shrinkflation detected)
2. Fake-Discount Verdict Score
Why use it? Compare the claimed discount against the typical price you've actually seen — get a verdict on whether the "sale" is real.
Key benefit: See through fake discounts and know if you're actually getting a deal.
formula
Claimed Original: $50, Sale Price: $35, Typical Price: $40
Claimed Discount: 30%, Real Discount: 12.5%
Gap: 17.5% → Likely Fake Discount
3. Subscribe & Save + Coupon Stacking Calculator
Why use it? See your true final price once every discount actually stacks — Subscribe & Save first, then your coupon.
Key benefit: Know exactly what you'll pay before you check out.
formula
Base Price: $50, Subscribe & Save: 15%, Coupon: $5 off
Price after S&S: $42.50, Final: $37.50
Total savings: $12.50 (25% off)
4. Warranty & Return-Window Tracker
Why use it? Track return deadlines and warranty expirations from your purchases.
Key benefit: Never miss a return window or warranty expiration again.
logic Calculates deadlines from purchase date and tracks status (Current / Upcoming / Overdue).
Item: "Laptop", Purchased: 2026-01-15
Return Window: 30 days → Deadline: 2026-02-14
Warranty: 12 months → Expiration: 2027-01-15
Today: 2026-06-15 → Return: Overdue, Warranty: Current
5. Marketplace Negotiation Assistant
Why use it? Enter comparable sold prices to get a suggested counter-offer for classifieds and marketplace items.
Key benefit: Make informed offers based on actual market data, not guesses.
formula Median Price (of comps) × Target Percentage
Comps: $200, $220, $180, $210, $190
Median: $200, Target: 90% of median
Suggested counter-offer: $180
6. Secondhand Item Theft-Registry Checker
Why use it? Check a serial number against official theft registries, then log what you found.
Key benefit: A structured audit trail of your theft registry checks — essential for due diligence.
architecture Safe by design: Links to official free registries (Bike Index, NICB VINCheck) and logs your findings — no embedded stolen-item data.
7. Healthcare Price Transparency Checker
Why use it? Log procedure prices you find in hospitals' published price transparency files.
Key benefit: Build a personal price reference for common procedures — see which hospital is cheaper.
8. Open Textbook / OER Alternative Finder
Why use it? Search official OER libraries (OpenStax, Open Textbook Library, MERLOT) for a free alternative before buying.
Key benefit: Save hundreds of dollars by finding free open-education alternatives.
9. Policy Renewal Price-Creep Alert
Why use it? Track your renewal price year over year and catch increases with no claims filed.
Key benefit: Catch "loyalty tax" price creep — know when to shop around.
formula Suspicious = Price Increase > 10% AND No Claims Filed
Policy: "Auto Insurance"
2025: $1,200, 2026: $1,400, No claims filed
Increase: 16.7% → Suspicious — shop around
10. Claim Documentation Timestamper
Why use it? Capture timestamped photos and notes for your insurance claim.
Key benefit: Organized, timestamped evidence — ready for your claim submission.
11. Coverage Gap Explainer
Why use it? A plain-language glossary of common policy exclusion terms.
Key benefit: Understand what your insurance actually covers — and what it doesn't.
Acts of God / Force Majeure: Natural events like earthquakes or floods, often excluded.
Wear and Tear: Gradual deterioration from normal use — almost always excluded.
Pre-Existing Condition: A condition that existed before the policy started — commonly excluded or limited.
12. DeFi Impermanent Loss Calculator
Why use it? Real-time impermanent loss for a 2-asset constant-product liquidity position.
Key benefit: Know your impermanent loss risk before providing liquidity.
formula IL = (2√k) / (1 + k) − 1, where k = current ratio / deposit ratio
Deposit Price Ratio: 1.00, Current Price Ratio: 2.00
k = 2.00, IL = -5.72%
→ You would have 5.72% less value than just holding
13. Cross-Chain Gas Cost Comparator
Why use it? Compare total bridging cost — not just gas — across routes.
Key benefit: See the true total cost of each route, including gas, bridge fees, and slippage.
formula Total Cost = Gas Fee + Bridge Fee + (Amount × Slippage %)
Route 1: Gas $5, Bridge $10, Amount $100, Slippage 0.5%
Total cost: $15.50 → Cheapest
Route 2: Gas $2, Bridge $20, Amount $100, Slippage 1.0%
Total cost: $23.00 → More expensive
Key User Pain Points & How This Toolkit Solves Them
Shrinkflation Tracker reveals the true cost-per-unit trend.
Fake-Discount Verdict reveals inflated claims and real savings.
Warranty Tracker shows countdowns so you never miss a deadline.
Policy Price-Creep Alert flags unjustified increases.
OER Finder links to free alternatives and logs what you found.
Impermanent Loss Calculator shows your exact IL risk.
Why Upgrade to Monthly Pro?
🚀 Unlock the full power of all 13 tools
The free tier gives you core functionality forever. But if you're serious about saving money and making smarter financial decisions, the Pro plan removes all limits and gives you advanced capabilities.
🆓 Free
- All 13 tools (core)
- 3 claim cases
- 5 gas routes
- Limited history
⭐ Pro
- Unlimited claim cases
- Unlimited gas routes
- Unlimited history
- Priority support
📈 ROI
- 💸 $5+/mo
- ⏱️ Saves 10+ hours/year
- 🛡️ Prevents overpaying
- 📊 Smarter decisions
14‑day free trial included · cancel anytime
Pricing: Free vs. Monthly Pro
- All 13 tools (core)
- 3 claim cases
- 5 gas routes
- Limited history
- Unlimited claim cases
- Unlimited gas routes
- Unlimited history
- Priority support
One Pro subscription covers all 13 tools. Get your license at muhiuddinalam.gumroad.com/l/dsjamr.
Data Privacy, Performance & Permissions
- 🔒 Local‑only storage: All data (shrinkflation logs, discount checks, warranty items, claim cases, gas routes) is stored exclusively in your browser using
chrome.storage.local. - ⚡ No background scraping: The extension only runs when you interact with it — no automatic data collection.
- 🛡️ Minimal permissions: Only
storage,alarms, andactiveTab— no browsing history access. - 🧪 Tested accuracy: All calculation engines have been tested against real-world scenarios.
Common Mistakes to Avoid
Fix: Always use the net weight or count — not the package weight. A 16oz box may contain 14oz of product.
Fix: Only enter prices you've personally observed from the same retailer — not manufacturer MSRPs which are often inflated.
Fix: IL is symmetric — price increase and price decrease of the same magnitude produce the same IL. The formula uses k = current/deposit ratio; if the ratio goes up 2x or down to 0.5x, both give the same IL.
- ⚠️ Shrinkflation: Log the same product consistently — use the exact same name each time.
- ⚠️ Fake Discount: The "Typical Price" field is your anchor — enter a price you've actually seen, not the sticker price.
- ⚠️ Impermanent Loss: The ratio is "Asset A relative to Asset B" — be consistent with which asset you're tracking.
- ⚠️ Gas Comparator: Enter your actual transfer amount — the total cost scales with the amount you're moving.
Frequently Asked Questions
Does the Theft-Registry Checker have its own stolen-item database?
No — and that's by design. Stolen-item databases are incomplete and change constantly. The tool links directly to official free registries (Bike Index, NICB VINCheck) and logs your findings for your own audit trail.
How accurate is the Impermanent Loss Calculator?
It uses the exact constant-product-AMM formula used by Uniswap and other major DEXs. The formula has been tested against the standard reference values: no price change → 0%, 2x change → -5.72%, 4x change → -20.00%, and symmetric behavior at 0.5x.
What's the difference between "Subscribe & Save" and a coupon?
Subscribe & Save is applied first (as a percentage off the base price), then the coupon is applied to the already-discounted price. This is how Amazon actually stacks these discounts.
What happens if I uninstall the extension?
All data (shrinkflation logs, discount checks, warranty items, claim cases, gas routes) is removed from your browser. If you have a Pro license, you can re-enter your key after reinstalling to restore access.
Ready to make smarter money decisions?
14-day free trial · $5+/mo covers all 13 tools · cancel anytime
Get Monthly Pro → Install Free on Chrome Web Store →Consumer Money & Shopping Toolkit · Version 1.0 · Built with ❤️ for Chrome · Privacy Policy · Contact Me
