How to Decode Multiple QR Codes Simultaneously in a Web App Without Latency
Meta Description
Scanning multiple QR codes in real-time without lag is finally possiblehere’s how I made it work in my web app using VeryUtils’ Barcode Scanner SDK.
Every QR code scan used to be a bottleneck
A few months ago, I was knee-deep in building an internal inventory tool for a client. They needed a way to check in products fastlike real fast. The old system? It relied on handheld scanners tied to desktop software, and scanning one item at a time felt like watching paint dry.
Imagine a warehouse floor buzzing with activity, workers trying to scan dozens of packages, and the scanner either misreads or lags… every… single… time. Frustrating doesn’t even begin to describe it.
That’s when I started digging. I needed something browser-based. Something my team could drop into the client’s web app and have it just workwithout latency, without downloads, and definitely without the old-school hardware.
And that’s when I found VeryUtils JavaScript Barcode Scanner SDK.
The tool that changed the game
VeryUtils JavaScript Barcode Scanner SDK isn’t just another barcode reader libraryit’s a beast.
This thing runs entirely in the browser and can decode multiple QR codes simultaneously from a live video stream. No native app. No painful setup. Just load the SDK, drop in a few lines of JavaScript, and boomyou’re scanning 20+ barcodes per second like a boss.
The best part? It works on anything with a cameralaptops, tablets, mobile phones.
The real-time performance is wild. I’ve used a bunch of barcode scanners over the years, but this one is in a league of its own.
Here’s how I actually used it
I was sceptical at firstthese tools always sound good on paper.
But I set up a quick POC using the video camera demo from their website. Just a basic HTML page, a script tag pointing to their minified JS file, and a call to decodeFromVideoDevice().
Here’s what stood out right away:
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Insane speed
This SDK scans over 500 barcodes per minute. I literally tested it by printing out a grid of QR codes and moving the camera over them. It read them like Neo reading the Matrix.
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Zero latency
The decoding happens almost instantly. I didn’t notice any of the jank or lag that you’d normally expect with browser-based tools. This thing leverages WebAssembly under the hoodit’s optimised to the teeth.
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Batch scanning actually works
Multiple QR codes on a screen? No problem. It picks up each one cleanly, outputs them, and doesn’t get tripped up even when some are partially obscured or tilted.
Who needs this?
If you’re building any kind of inventory management tool, event check-in app, logistics dashboard, or even a progressive web app for field agents, this SDK is gold.
It’s especially clutch when:
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You don’t want users to install anything.
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You’re targeting mobile-first experiences.
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Your users need fast throughput without errors.
In my case, the client didn’t want to spend on hardware scanners. They wanted their people to walk the warehouse with tablets, scan QR codes, and be done.
This SDK nailed it.
Why VeryUtils > everyone else
I tried some open-source libraries firstyou know the onesand they’re fine… until you throw a dozen QR codes at them or try decoding on older Android phones.
That’s when the wheels fall off.
With VeryUtils, here’s what I got:
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No app install.
Just launch the browser and start scanning.
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Runs offline.
Yep, it supports PWA environments, so I could cache everything and make it work without a steady internet connection.
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Works across environments.
I tested it on Safari, Chrome, and even Firefox on mobile. No hiccups.
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High accuracy.
Even under poor lighting or wrinkled labels, the scanner nailed it with a near 99% recognition rate.
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Secure as hell.
Since it doesn’t require any server processing, there are no data privacy issues. That’s a massive plus for apps handling sensitive documents or medical data.
More features that blew me away
Let’s bullet it out because this thing’s stacked:
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User guidance Visual and audio feedback helps non-tech users know when a scan’s successful.
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OCR support You can even scan barcodes embedded in scanned documents or images.
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Supports all major formats From 1D barcodes like Code 128 and EAN-13 to 2D like QR Code, DataMatrix, and PDF417.
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Decode from anything Not just live videoalso works on image uploads, base64 images, and raw image data.
My final verdict
I’m not going back to clunky barcode toolsever.
VeryUtils JavaScript Barcode Scanner SDK let me build a real-time, multi-code scanning tool inside a basic web app that performs like an enterprise-grade platform.
It saved my client thousands in hardware costs.
And saved me hours of debugging.
If you’re in the trenches building fast, scalable web tools that involve scanning, this is the SDK you want.
I’d recommend this to anyone dealing with barcodes or QR codes at scale.
Try it for yourself:
Click here to get started with the SDK
Need Something Custom? VeryUtils Has You Covered
If your use case is a bit out of the boxor you need deep integrationsVeryUtils also does custom development.
Whether it’s building Windows virtual printers, adding barcode recognition into a POS, or intercepting file access with Windows APIs, they’ve done it.
They build tools for:
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PDF and document processing across Windows, Linux, macOS
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Custom virtual printer drivers (PDF, EMF, TIFF, etc.)
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System-wide API hooks for monitoring or modifying behaviour
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OCR, layout analysis, barcode reading/generation
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Cloud-based document conversion, security, and signature solutions
They even offer true type font tech, DRM protection, and office printing systems.
You can hit them up through their support portal if you need something tailored to your workflow.
FAQs
How many QR codes can it scan at once?
Up to 20 codes per second from live video input, depending on device performance and camera quality.
Does it work offline?
Yes. With PWA support, your app can scan even with limited or no internet connection.
Is there a mobile SDK?
You don’t need one. This is a web SDK, and it works on mobile browsers right out of the box.
Can I scan from an uploaded image?
Absolutely. You can decode from images, base64 strings, or raw image data, not just video.
Do I need to install anything to use it?
Nope. It’s browser-basedjust include the JS file, and you’re good to go.
Tags / Keywords
javascript barcode scanner
decode multiple QR codes simultaneously
qr code scanner web app
real-time barcode scanning SDK
VeryUtils JavaScript Barcode Scanner
And yeah“how to decode multiple QR codes simultaneously in a web app without latency” is not just a catchy title. It’s exactly what this SDK helps you do. Fast, clean, and with zero drama.