How to Evaluate Startup Equity: A Software Engineer's Guide
How to Evaluate Startup Equity: A Software Engineer's Guide
Most engineers evaluate startup equity by staring at a share count. That's almost useless information. Here's what to look at instead.
You just got an offer from a Series B startup. The base is $180K — $70K below the FAANG offer you're comparing it to. But they're giving you 50,000 shares vesting over four years.
The recruiter says the company was last valued at $500M. You do the math: $500M valuation, 50,000 shares, and... you realize you have no idea how many total shares exist, what happens to your shares if they raise again, or whether "valued at $500M" means anything for what you'd actually receive in an exit.
This is the exact moment most engineers make an expensive mistake — either overvaluing the equity because the numbers sound large, or dismissing it because the analysis feels too complicated.
The startup equity calculation isn't complicated, but it requires asking the right questions. Here's the framework.
RSUs vs. Stock Options: The Fundamental Difference
Before anything else, identify what you're actually receiving. This determines the entire analysis.
RSUs (Restricted Stock Units) are what FAANG companies primarily grant. They're units that convert to actual shares on a vesting schedule. Their value is straightforward: vested shares × current stock price. No decision required to exercise. No tax complexity at grant time.
Stock Options (ISOs or NSOs) are what most startups grant. These are the right to buy shares at a fixed "strike price" — the fair market value at the time of grant. Your profit is the spread between the strike price and the eventual sale price, minus taxes. Unlike RSUs, they require an active decision to exercise, and exercising costs money.
At a private startup, both types are illiquid until an exit event (IPO, acquisition, or secondary sale). The difference in tax treatment is significant, which brings us to the next distinction.
ISOs vs. NSOs: Which Type of Option You Have Matters
Most startup engineers receive Incentive Stock Options (ISOs), which carry preferential tax treatment under U.S. law — qualifying dispositions can be taxed at long-term capital gains rates rather than ordinary income rates. ISOs can only be granted to employees (not contractors), and there's a $100K annual limit on options that can become exercisable in a single year.
Non-Qualified Stock Options (NSOs) are taxed as ordinary income at exercise on the spread between strike price and fair market value — regardless of whether you've sold the shares. This creates a potential tax liability the moment you exercise, even if the stock is illiquid.
If you're being offered NSOs and you're a full-time employee, ask why. Valid reasons exist (large grants that exceed the ISO limit, or certain corporate structures), but it's worth understanding.
One critical tax move most engineers miss: the 83(b) election. If you're granted restricted stock (common for very early hires) or early-exercisable options, you can elect to pay tax on the value at grant time rather than at vest. If the company's value rises significantly, this can save enormous amounts in taxes. The election must be filed with the IRS within 30 days of grant. If the company doesn't proactively mention it, ask.
The Number That Actually Matters: Ownership Percentage
Ignore the share count. Ask for your ownership percentage on a fully diluted basis.
"Fully diluted" means accounting for all shares that could exist: common stock, preferred stock, all outstanding options, all options in the option pool (whether granted or not), warrants, and convertible notes that will convert to equity.
According to Carta's equity data, typical ownership percentages by hire number look roughly like this:
| Hire Number | Typical Equity Range | |-------------|---------------------| | Engineer hire #1–3 | 0.5%–1.5% | | Engineer hire #5–10 | 0.1%–0.5% | | Engineer hire #10–25 | 0.05%–0.2% | | Engineer hire #25+ | 0.01%–0.1% |
If the company won't tell you the total fully diluted share count, that is a red flag. You cannot evaluate an equity offer without this number. Period.
What the 409A Valuation Tells You (And What It Doesn't)
The 409A valuation is an IRS-mandated independent appraisal of a company's common stock fair market value. It's what sets your option strike price. Understanding it reveals a counterintuitive truth about startup equity.
At a startup, common stock is worth significantly less than preferred stock. The most recent preferred share price (used to calculate that impressive "$500M valuation" headline) reflects what investors paid for shares with special rights — liquidation preferences, anti-dilution provisions, and priority on exit proceeds. Common stock, which is what your options convert to, has none of those protections.
Per Sofer Advisors' 2026 409A guide, common stock is typically valued at 20–40% of the preferred share price at early stages, using valuation methodologies that treat preferred preferences as prior claims. This discount is real and it matters for your exit math.
Practical implication: if a startup's Series B preferred is priced at $10/share and they're telling you the company is worth $500M, your common stock strike price might be $3–4/share via the 409A. That's actually good news for options (lower strike = more upside), but the valuation headline should not be interpreted as the price at which common shareholders benefit.
Liquidation Preferences: Why Your Exit Math Is More Complex Than It Looks
This is the piece most engineers skip — and the most important one for evaluating whether equity is actually worth taking lower cash for.
Liquidation preferences are terms on preferred stock that give investors the right to receive their money back (and often more) before common shareholders receive anything in an exit.
A standard 1x non-participating liquidation preference means investors get their invested capital back before anyone else. If a company raised $40M across its funding rounds, investors collect $40M first. Only proceeds above that threshold flow to common shareholders (option holders).
More punitive structures include:
- 1x participating preferred: Investors get their money back plus their pro-rata share of remaining proceeds
- 2x liquidation preference: Investors get 2× their invested capital before common shareholders see anything
The practical framework from Paraform's 2026 equity guide: before modeling your equity upside, calculate the "liquidation preference stack" — the total capital raised that must be returned first. If a company has raised $200M and is acquired for $250M, common shareholders split only $50M. At a 0.1% fully diluted stake, your pre-tax payout is $50K, not the $250K the headline acquisition price suggests.
The questions to ask:
- What is the total capital raised to date?
- What are the liquidation preferences on each preferred series?
- Are they participating or non-participating?
- What is the total liquidation preference stack?
Many companies and recruiters genuinely don't know these details off the top of their heads. That's fine — ask them to check with the CFO or legal team. A well-run company will answer. A company that deflects is telling you something.
Dilution: Your Stake Today Is Not Your Stake at Exit
Every future funding round will dilute your ownership percentage. Understanding the typical magnitude of this dilution is essential for realistic exit modeling.
Research from Qubit Capital on funding round dilution benchmarks:
| Round | Typical Dilution | |-------|-----------------| | Seed | 15–25% | | Series A | 15–25% | | Series B | 10–20% | | Series C+ | 10–15% |
A cumulative dilution example: you join at Series A with 0.2% ownership. The company raises a Series B (20% dilution) and Series C (15% dilution). Your stake becomes approximately 0.2% × 0.80 × 0.85 = 0.136%. If an option pool refresh is added for new hires, further dilution applies.
Most startups will also refresh option grants for retained employees and raise additional funding before any exit event. A realistic model assumes 2–4 more funding rounds from wherever you're joining, meaning 30–50% cumulative additional dilution from today's ownership percentage.
Run the math at the offer stage, not the offer-signing stage.
The Decision Framework: Early-Stage vs. Growth-Stage Offers
The right question to ask about startup equity isn't "is this equity worth something?" — it's "does the expected value justify the cash salary gap?"
For early-stage (Seed to Series A)
Higher equity upside, higher probability of zero. Research on VC-backed startup outcomes consistently shows most equity for employee-level investors does not result in meaningful liquidity.
Run three scenarios:
Base case (modest outcome): Company sells for 3–5× last valuation. Does your equity net positive after dilution and liquidation preferences?
Good case (strong exit): Company sells for 8–10× last valuation or IPOs at a premium. What's the per-share value after preferences clear?
Failure case (most common): Equity is worth zero. Is the base salary livable? Is the experience and network worth it?
If the good case result after dilution and preferences doesn't materially compensate for the cash gap versus a comparable FAANG offer over 4 years, the equity upside isn't priced right for the risk you're taking.
For growth-stage (Series C to pre-IPO)
Liquidation preferences are more likely to be cleared in a successful exit because the exit price required to do so is lower relative to valuation. The probability of some liquidity is higher. But the equity percentage you receive is also much smaller, and the valuation you're granted at is much higher.
At late-stage pre-IPO companies, treat the equity more like discounted RSUs than a lottery ticket. The AI Startup vs. FAANG comparison from Recruiting from Scratch notes that late-stage AI startups are offering $160K–$250K base plus equity — still a gap versus top FAANG packages ($350K–$450K+ total comp), but the equity risk premium is more comprehensible when you can see a credible path to liquidity.
Red Flags in Startup Equity Offers
- "We'll give you X shares" with no disclosure of total shares outstanding. Non-negotiable ask: get the fully diluted share count.
- Company won't disclose total capital raised or liquidation preference structure. Public companies file this. Private companies that won't share it are hiding something relevant to your analysis.
- Offer letter mentions options but doesn't specify ISO or NSO. This should be explicit in the written offer. Ask before signing.
- No mention of exercise window. Standard is 90 days post-termination to exercise. Some employee-friendly companies have extended to 5–10 years. Short windows can force costly tax decisions if you leave.
- Option pool percentage is unusually large (30%+). Check how much has been granted vs. reserved. A large ungranted pool means significant future dilution for all current employees.
- Verbal promises about future grants or "we're planning to refresh next year." Nothing that isn't in your offer letter is enforceable. Get it in writing.
Putting It Together: The Questions to Ask Before You Sign
Before accepting a startup offer with meaningful equity as a component, get answers to these specific questions:
- What is the total fully diluted share count?
- What is my ownership percentage on a fully diluted basis?
- What is the total capital raised to date?
- What is the liquidation preference structure on each preferred series?
- Are my options ISOs or NSOs?
- What is the exercise window after termination?
- Has the 83(b) election been discussed? (If you're receiving restricted stock or early-exercisable options.)
- Does the company do annual refreshes for existing employees?
Most startups will answer all of these — some more readily than others. A well-run company treats this as standard diligence, not pushback.
TL;DR
- Shares mean nothing without total share count. Always get your ownership as a percentage of fully diluted shares.
- The preferred price headline is not your exit price. 409A common stock value is typically 20–40% of preferred — and preferred liquidation preferences are paid first in any exit.
- Model dilution. Expect 30–50% cumulative dilution from future rounds before any exit.
- ISOs are better than NSOs. Know which you have and understand the tax treatment at exercise.
- Early-exercisable options + 83(b) election. If applicable, file within 30 days of grant. Don't skip this.
- Run three scenarios. Base case, good case, failure case. Does the expected value justify the cash gap?
- Red flags are real. If the company won't answer basic structural questions, that's signal.
Startup equity is not fake — but it's not simple either. The engineers who do well by it are the ones who did the analysis before signing, not after.
Related: The Engineer's Salary Negotiation Playbook — before evaluating equity, know your market rate for the base salary comparison.
Related: How to Play Multiple Job Offers Against Each Other — when you have a startup offer and a FAANG offer simultaneously, this is how to run the process.
Related: Startup vs. Big Tech Resume: How to Position Your Experience — how the company you choose shapes the career narrative you'll write next.
Building the profile that gives you more leverage in every offer conversation — including startup equity negotiations — is exactly what Wrok is built for. Start your career profile on Wrok →