How to Use Keycode Checker (2026): Free Online Tool Guide
Stop guessing which event key you need. Here's how to capture every keystroke perfectly without opening the console every five seconds.
Marcus Thorne
Senior Frontend Architect
I spent about 42 minutes last Tuesday—not even joking, I timed it—staring at a line of JavaScript that refused to recognize a simple "Enter" key press on a client's legacy form. I was using some outdated reference sheet I found on a random forum from 2018, and it turns out, the "which" property I was relying on was behaving differently in Safari than in Chrome. Honestly, it's those little things that make you want to throw your mechanical keyboard out the window. That's exactly why having a reliable keycode checker is a non-negotiable for any dev working with DOM events.
Look, we've all been there. You're building a custom dropdown, a game, or maybe a shortcut system for a SaaS app. You need to know if the user hit Escape, or if they're holding down Shift while pressing 'Z'. You could write console.log(event) and dig through the massive object in your DevTools, but that's slow. It's tedious. And let’s be real, it's just plain annoying when you're in the flow.
What actually is a keycode checker?
Basically, a keycode checker is a simple utility that listens for keyboard events and spits out the data associated with them in real-time. When you press a key, the browser generates an object. This object contains several pieces of information: the physical key you pressed (code), the character it represents (key), and those old-school numeric values (keyCode and which).
Between you and me, the "old-school" numeric codes are actually deprecated. But—and this is a big "but"—we still have to deal with them because of legacy codebases and certain older browsers that just won't die. A free keycode checker no login required tool like the one we have here at SimpliConvert gives you all that info at once. You just hit a key, and boom, the data is there. No friction.
Key Takeaway
The best keycode checker 2026 edition should show you event.key, event.code, and event.keyCode simultaneously. This ensures your app works on both modern frameworks and older legacy systems without you having to double-check MDN documentation every time.
Why use our keycode checker tool?
I’ve used keycode.info for years. It was the gold standard. But lately, I’ve found I need a bit more, specifically when dealing with modifier keys like Meta (Command on Mac) or handling specific localized keyboard layouts. When we built the keycode checker at SimpliConvert, we wanted to make it the most robust keycode checker for Developers on the web.
It doesn't just show you the number 13 for "Enter." It tells you if shiftKey was true, if the location was on the Numpad, and it even helps you identify those tricky keys like "Dead" keys used in accents. It’s about saving those precious seconds that add up over a workday.
The "Mistake I Made" Corner
Once, I spent $47.50 on a "premium" UI library only to find out their keyboard navigation was hardcoded to keyCode values. It broke for my French users because their 'A' and 'Q' keys are swapped. Use event.key for characters and event.code for physical locations to avoid this!
Pro Tip
If you're building a calculator app, use our age in days calculator for logic inspiration, but for the input handling, always check the location property in our keycode tool to distinguish between top-row numbers and Numpad numbers.
How to use keycode checker: A quick tutorial
Using the tool is about as straightforward as it gets. You don't need a PhD in Computer Science for this.
- First off, navigate to the keycode checker page.
- Then, simply click anywhere on the screen to ensure the window has focus. This is a common trip-up—if your cursor is still in the address bar, the tool won't hear your keys!
- Press any key on your keyboard. Try a simple one first, like 'A'.
- Look at the cards that appear. You'll see the Key (what character is produced), the Code (the physical button pressed), and the Which/KeyCode (the legacy number).
- Finally, try a combination. Hold
Ctrl + Alt + DelorShift + Tab. You'll see the modifier status update in real-time.
It’s literally that simple. No logins, no "subscribe to our newsletter" popups blocking your view at 3:00 AM when you're tired and grumpy. Just the data you need.
Manual Debugging vs. Using SimpliConvert
You might be thinking, "Marcus, I can just write a listener in my code." Sure, you can. But let's look at why that's usually a waste of time compared to using a dedicated keycode checker tutorial-approved tool.
| Feature | Manual console.log | SimpliConvert Tool |
|---|---|---|
| Setup Time | 2-3 minutes (write, save, refresh) | Instant (0 seconds) |
| Modifier Detection | Manual object drilling | Visual indicators |
| Deprecated Info | Hidden in properties | Highlighted for legacy use |
| Mobile Support | Requires remote debugging | Works on mobile keyboards |
Common Mistakes to Avoid
One big thing I see juniors do all the time is confusing event.key and event.code. If you press the 'S' key, key is "s", but code is "KeyS". If you press 'S' while holding Shift, key becomes "S" (uppercase), but code stays "KeyS".
And don't get me started on the keyCode 229 bug on Android. If you're building for mobile, you'll see that many virtual keyboards just return 229 for everything. It's a nightmare. Our keycode checker helps you identify these quirks by showing you exactly what the browser is reporting in different environments.
Anyway, if you're ever feeling overwhelmed by string lengths or date formats while you're deep in the logic, you can always check out our YouTube title character counter or use the ISO date converter to clean up your data. We've got a whole suite of these little lifesavers.
Why is this relevant in 2026?
You'd think by now we'd have a universal way of handling inputs. But with the rise of new input devices, foldable screens, and complex web-based IDEs, keyboard events are more complex than ever. Whether you're a seasoned pro or just starting out, using a keycode checker saves you from the "it works on my machine" syndrome.
So yeah, quit guessing. Stop writing throwaway console.log statements that you'll inevitably forget to delete before your PR review (we've all been there). Just use the tool. It's faster, cleaner, and honestly, just a better way to work.
Frequently Asked Questions
Is event.keyCode actually deprecated?
Yes, event.keyCode is technically deprecated in the modern DOM spec. You should use event.key or event.code instead. However, many legacy apps and some specific game engines still rely on these numeric values, which is why our keycode checker still provides them.
What is the difference between Key and Code?
The key property represents the character generated by the keystroke (e.g., 'A' or 'a'). The code property represents the physical key on the keyboard (e.g., 'KeyA'), regardless of modifiers like Shift or keyboard layout (QWERTY vs AZERTY).
Why does my keycode checker not work on mobile?
Mobile browsers handle input differently, often using an Input Method Editor (IME). This frequently results in a generic keycode of 229. For mobile, it's often better to listen for input events rather than keydown if you need to capture text.
Do I need to install anything to use this?
Nope. This is a free keycode checker no login required tool. It runs entirely in your browser. If you need other text utilities, you might also like our random text generator for filling out your UI mocks.