Why Most Tech Workers Get Hit With a Surprise RSU Tax Bill (And How to Fix It)

Jonathan — Thu, 27 Aug 2026 14:47:17 +0000

If you receive RSUs as part of your compensation package, there is a hidden tax mechanism that quietly catches thousands of software engineers off guard every single April.

Here is why the math breaks down and how to avoid an unexpected four-figure IRS bill.

The 22% Supplemental Tax Trap

When your RSUs vest, your employer's broker automatically withholds shares to cover taxes. By default, federal tax guidelines apply a flat 22% supplemental withholding rate on these vested shares.

If your total taxable income puts you in the 32%, 35%, or 37% federal bracket, your broker is under-withholding by 10% to 15% on every single vest.

The Reality Check: On a $50,000 annual RSU vest, a 13% tax gap leaves you with a $6,500 silent tax debt by the end of the year.
The Penalty Compound: If you owe more than $1,000 at tax time without hitting IRS Safe Harbor rules, you get hit with underpayment penalties on top of what you already owe.

3 Steps to Protect Yourself

Calculate Your True Marginal Rate: Base salary + bonus + total vested equity value = your real top-line tax bracket.
Adjust Withholding or Pay Quarterly: Request extra withholding on your W-4 base salary or submit quarterly estimated payments directly to the IRS.
Never Budget on Gross Equity: Always project your financial plans on the after-tax net amount.

Why I Built a Calculator for This

Tired of running these numbers on manual spreadsheets every quarter, I built a free, lightweight tool called VestingGap.

It lets you plug in your base salary, filing status and vesting schedule to instantly project your effective tax shortfall before the IRS bill arrives. No ads, no signup needed—just quick math for tech workers.

How do you usually handle tax withholdings on your vesting schedules? Let's discuss in the comments!

Why I build a 100% In-Browser HEIC Converter with WebAssembly (Bye Bye Cloud Server Upload! 🚀)

Jonathan — Wed, 19 Aug 2026 17:21:36 +0000

Hey DEV community! 👋

If you use an iPhone or Mac alongside Windows or Android, you've definitely run into this frustrating scenario: You transfer a bunch of .heic photos to your PC, only to realize half your apps can't open them. 😤

Naturally, you Google "HEIC to JPG converter" and click the first few results. But then the red flags start showing up:

🚨 Privacy Concerns: You're uploading personal or confidential photos to unknown third-party servers.
⏳ Bandwidth Bottlenecks: Uploading 50+ high-res iPhone photos takes forever on standard internet connections.
💳 Paywalls & Limits: "You've reached your limit of 5 conversions today. Upgrade to Pro!" 🙄

I got sick of this dance, so I decided to build my own solution: PixHeic.

💡 The Core Idea: 100% Client-Side Processing

Instead of shipping your image bytes over the internet to a heavy backend server, why not make the user's browser do all the heavy lifting?

Modern browsers are ridiculously powerful. By combining WebAssembly (Wasm) and the native HTML5 Canvas API, we can run desktop-class image processing right inside the tab.

Here is the entire data flow in a nutshell:

[ User File (HEIC) ]
│
▼
[ WebAssembly Engine (In-Browser Decoding) ]
│
▼
[ HTML5 Canvas Buffer ]
│
▼
[ Export to JPG / PNG / WebP ]
│
▼
[ Instant Local Download ]

🛠️ Why WebAssembly is a Game-Changer Here

Decoding raw ⁠.heic⁠ container structures purely in JS used to be sluggish. By compiling low-level image decoding libraries into WebAssembly, we get near-native execution speed directly in the browser sandbox.

The Benefits:
🔒 Zero Data Exposures: Photos literally never leave your device memory. You can even disconnect your internet and the app keeps converting!

⚡ Lightning Fast: No upload/download wait times. Processing is limited only by your local CPU.

🆓 No Daily Batch Caps: Since there are no cloud server bandwidth costs to cover, batch converting 100+ files remains completely free.

🚀 Try It Out & Feedback Welcome!

You can test the tool live here: pixheic.com

And the open repository is on GitHub: GitHub
I'd love to hear your thoughts! How are you handling heavy browser-side tasks in your own web apps? Any Wasm performance tweaks you'd recommend?

Happy coding! 💻✨

DEV Community: Jonathan

Why Most Tech Workers Get Hit With a Surprise RSU Tax Bill (And How to Fix It)

Why I build a 100% In-Browser HEIC Converter with WebAssembly (Bye Bye Cloud Server Upload! 🚀)

💡 The Core Idea: 100% Client-Side Processing

🛠️ Why WebAssembly is a Game-Changer Here

🚀 Try It Out & Feedback Welcome!