When a restock drops and you have less than 30 seconds to complete checkout, your manual typing speed is the bottleneck. Auto-checkout and auto-fill browser extensions solve this problem by pre-loading your payment and shipping information and automating as much of the checkout flow as possible. Here is a thorough breakdown of the best options available in 2026.
Important Disclaimer First
There is a meaningful distinction between auto-fill extensions (which pre-populate your information into checkout forms) and auto-checkout bots (which autonomously complete purchases without human input). This guide focuses on the former category. Auto-fill tools are legal, widely used, and ethically acceptable. Fully autonomous checkout bots exist in a legal gray area and are banned by most retailers’ terms of service. We do not recommend or endorse bot usage.
Extension Comparison
| Extension | Browser Support | Auto-Fill | One-Click Checkout | Price Alerts | Free Tier | Paid Tier |
|---|---|---|---|---|---|---|
| Autofill by Fillr | Chrome, Edge, Firefox | Yes | No | No | Full features free | N/A |
| 1Password | Chrome, Edge, Firefox, Safari | Yes | No | No | Free (limited) | $3/mo |
| Dashlane | Chrome, Edge, Firefox, Safari | Yes | No | No | Free (limited) | $4.99/mo |
| Honey | Chrome, Edge, Firefox, Safari | Yes | No | Yes | Full features free | N/A |
| Capital One Shopping | Chrome, Edge, Firefox | Yes | No | Yes | Full features free | N/A |
| Swift Checkout | Chrome | Yes | Yes (select retailers) | Yes | Basic free | $5/mo |
| FastFingers | Chrome, Edge | Yes | Yes (select retailers) | No | Basic free | $8/mo |
Detailed Reviews
Autofill by Fillr - Best Free Option
Fillr has been around since 2015 and does one thing extremely well: it fills in forms fast. It supports multiple profiles so you can store payment and shipping information for different addresses or cards. When a checkout page loads, Fillr detects form fields and populates them instantly.
Pros:
- Completely free with no feature gates
- Fastest form detection among the extensions tested
- Supports multiple profiles for different shipping addresses
- Works on virtually every retail site
- Lightweight, does not slow down your browser
Cons:
- No auto-click or auto-submit functionality
- No price tracking or restock alerts
- Has not been updated as frequently as competitors
Best for: Users who want a reliable, free, no-frills auto-fill tool.
1Password and Dashlane - Best for Security-Conscious Users
Password managers like 1Password and Dashlane are not specifically designed for restock drops, but their form-filling capabilities are excellent. They store credit card numbers, addresses, and identity information in encrypted vaults and auto-fill checkout forms across any website.
Why consider a password manager for restocks:
- Your payment data is encrypted and stored securely, unlike some dedicated auto-fill tools
- Cross-device sync means your profiles work on phone, tablet, and desktop
- You need a password manager anyway, so this avoids installing an extra extension
Limitations for restocks:
- Form detection is slightly slower than dedicated auto-fill tools (about 0.5-1 second difference)
- No restock-specific features like alerts or one-click checkout
- Occasional misidentification of form fields on unusual checkout pages
Honey - Best All-Rounder
Honey (owned by PayPal) combines coupon auto-application with auto-fill and price tracking. While it is not as fast as Fillr for pure form-filling, it adds significant value with its coupon database and price history features.
Standout features:
- Automatically applies coupon codes at checkout, saving an average of $4-8 per transaction
- Droplist feature tracks prices on specific products and notifies you of drops
- Amazon price history integration shows 30/60/90-day price trends
- PayPal integration for faster checkout on supported sites
Limitations:
- Slightly slower auto-fill compared to Fillr (noticeable during competitive drops)
- Coupon testing adds 10-30 seconds to checkout, which you should disable during restock drops
- Collects browsing data (as outlined in their privacy policy)
Tip: If you use Honey during restock drops, disable the automatic coupon feature temporarily. You can do this by clicking the Honey icon and toggling off “Automatically apply coupons.” The extra seconds it takes to test codes can cost you a limited item.
Swift Checkout - Best for Serious Restockers
Swift Checkout is specifically designed for competitive purchasing. It goes beyond auto-fill by offering configurable one-click checkout flows for specific retailers.
How it works:
- You set up a profile with your payment and shipping information
- You configure “checkout flows” for specific retailers (Best Buy, Target, Walmart, etc.)
- When you click the Swift Checkout button on a product page, it executes the entire add-to-cart and checkout process in rapid sequence
- You confirm the final purchase with a single click
Retailer-specific support includes:
- Best Buy: Add to cart, proceed to checkout, apply auto-fill, place order
- Target: Add to cart, select shipping method, apply auto-fill, confirm
- Walmart: Add to cart, skip Walmart+ prompt, checkout, apply auto-fill
- Amazon: Limited support due to Amazon’s anti-automation measures
Pros:
- Measurably faster than manual checkout (5-8 seconds vs. 15-25 seconds)
- Retailer-specific flows handle each site’s quirks
- Does not violate retailer TOS because it requires human initiation
Cons:
- $5/month for the paid tier, which unlocks most retailers
- Chrome only as of early 2026
- Retailer flows break when sites update their checkout pages, requiring extension updates
- Amazon support is limited
FastFingers - Best for Multi-Site Monitoring
FastFingers combines auto-fill with a built-in stock monitoring dashboard. You can add product URLs from multiple retailers and FastFingers will poll them periodically, alerting you when items come back in stock.
Unique features:
- Built-in stock monitor that checks product pages every 30-60 seconds
- Desktop notifications when monitored items restock
- Auto-opens the product page when stock is detected
- Checkout flow automation for select retailers
Limitations:
- $8/month is the most expensive option in this roundup
- Stock monitoring interval (30-60 seconds) is slower than dedicated services like HotStock
- Higher resource usage due to background monitoring
- Chrome and Edge only
Setup Tips for Maximum Speed
Regardless of which extension you choose, these configuration tips will help you check out as fast as possible during drops:
1. Pre-Fill Everything
Do not just save your credit card number. Save your:
- Full name (exactly as it appears on your card)
- Billing address
- Shipping address
- Phone number
- Email address
Some checkout forms have 8-12 fields. Every field the extension fills automatically is one less point of failure.
2. Use a Credit Card, Not Debit
Credit cards offer chargeback protection if something goes wrong. They also tend to process faster during checkout because they do not require real-time bank balance verification.
3. Disable Other Extensions During Drops
Ad blockers, privacy extensions, and other tools can interfere with checkout flows. If you are going into a competitive drop, temporarily disable everything except your auto-fill extension and your restock alert tool. A clean browser profile dedicated to restock drops is even better.
4. Use a Wired Internet Connection
Wi-Fi adds latency and introduces the possibility of connection drops at the worst moment. If you are serious about restocks, plug in an ethernet cable. The difference is typically 5-15ms of latency, which adds up across multiple page loads.
5. Keep Your Extension Updated
Retailer websites change constantly. Auto-fill and auto-checkout extensions need regular updates to keep their form detection and checkout flows working. Enable auto-updates and check for updates manually before a known drop.
The Bottom Line
For most people, Autofill by Fillr or Honey provides enough speed improvement to meaningfully increase your success rate during restocks, and both are free. If you are regularly competing for limited drops and want every possible advantage, Swift Checkout at $5/month offers the best combination of speed and reliability. Password managers like 1Password are a solid choice if you already use one and do not want another extension in your browser.
The key takeaway: any auto-fill tool is dramatically better than typing your information manually. Even the simplest extension shaves 10-15 seconds off checkout, and in the restock game, those seconds are everything.
