How to Create a Cap Table That Won't Blow Up in Your Face

What is a cap table?

A capitalisation table (cap table) is a record of who owns what in your company. It tracks every share, option, SAFE, and convertible note, and shows the ownership percentage for each stakeholder.

At its simplest, a cap table has three columns:

That's a Day 1 cap table. Two cofounders, equal split, 10 million shares. Clean and simple.

But cap tables get complicated fast. Every time you issue equity - to a cofounder, an employee, an advisor, or an investor - the table changes. SAFEs and convertible notes sit off to the side until they convert, at which point they dilute everyone.

The cap table is the single source of truth for ownership. If it's wrong, everything built on top of it is wrong - investor negotiations, employee option grants, founder ownership calculations, exit scenarios.

Building your first cap table

When you incorporate, you issue a set number of shares (the "authorised shares"). Common numbers are 10 million or 100 million. The exact number doesn't matter much - what matters is the percentages.

Step 1: Founder shares

Decide on the founder split and issue shares accordingly. If two cofounders split 50/50 with 10 million total shares, each gets 5 million.

If the split is 60/40, Founder A gets 6 million and Founder B gets 4 million.

Step 2: ESOP (Employee Share Option Pool)

Most startups set aside 10-15% of shares for an employee option pool. This is equity reserved for future hires.

With a 10% ESOP on 10 million shares, you'd reserve 1 million shares. The cap table now looks like:

Important: The ESOP dilutes the founders equally. When investors come in later, they'll typically want the ESOP to come from the founders' shares, not from the investor's allocation. Understand this upfront.

Step 3: Advisor shares

If you bring on advisors who receive equity (typically 0.25-1% each), add them to the table. These usually vest over 1-2 years.

Adding SAFEs and convertible notes

This is where most founders get confused - and where the real mistakes happen.

SAFEs and convertible notes don't appear on your cap table as equity immediately. They sit in a separate section - often called "convertible instruments" or "notes outstanding" - until a conversion event happens (usually a priced round).

You need to track them anyway. Create a section in your cap table that lists: - Investor name - Instrument type (SAFE or convertible note) - Amount invested - Valuation cap - Discount (if any) - Date signed - Pre-money or post-money

When the priced round happens, all these instruments convert into actual shares. The conversion maths depends on whether the SAFE is pre-money or post-money, and the specific terms of each note.

This is where even lawyers make mistakes. I'm not exaggerating - I've seen legal counsel get the conversion wrong because they weren't careful with the pre-money vs post-money distinction. The maths is not intuitive, especially when you have multiple SAFEs at different caps.

My strong recommendation: use a cap table management tool. In Australia, Cake Equity is excellent for this. Internationally, Carta is the standard. These tools handle the conversion maths automatically, which removes the human error that causes so many problems.

If you're too early for a paid tool, AI can genuinely help here too. You can plug your SAFE terms into Claude or ChatGPT and ask it to model the conversion scenario. It's remarkably good at this, and it gives you a second check on the maths.

The SAFE conversion problem

Let me walk through why SAFE conversion is the number one source of cap table errors.

Say you have two SAFEs: - SAFE 1: $100K at a $2M post-money cap - SAFE 2: $200K at a $4M post-money cap

Now you raise a Series A at $8M pre-money, $2M investment, $10M post-money.

SAFE 1 converts: $100K / $2M cap = 5% ownership

SAFE 2 converts: $200K / $4M cap = 5% ownership

Series A investor gets: $2M / $10M post-money = 20%

But wait: Is the 5% calculated before or after the Series A shares are issued? Does the ESOP come out of the pre-money? How do the SAFEs interact with each other?

This is where founders who haven't modelled it out get blindsided. They expected to own 60% after the round, but the actual number is 52%. Or 48%. The specifics depend on the exact terms of each instrument, and small differences compound.

The fix is simple but non-negotiable: model every conversion before the priced round. Not after. Not during. Before. Sit down with your lawyer and your cap table tool, plug in every SAFE and note, and run the conversion scenario at your expected Series A valuation. Then run it at a lower valuation and a higher valuation, because the conversion maths changes at different price points.

The option pool shuffle

Investors at the priced round stage almost always want an ESOP (employee stock option pool) in place. The negotiation question is: does the ESOP come from the pre-money or post-money valuation?

Pre-money ESOP (most common): The option pool is created before the investor's money comes in. This means the founders absorb all the dilution from the ESOP. A $10M pre-money valuation with a 15% ESOP means the founders' effective pre-money value is really $8.5M.

Post-money ESOP (less common, founder-friendly): The option pool is created after the investment, so the dilution is shared between founders and investors.

Most investors will push for a pre-money ESOP because it maximises their ownership percentage. As a founder, you need to understand this dynamic and factor it into your cap table projections.

A common mistake: Founders agree to a 15% ESOP without realising how much it dilutes them. If you already have a 10% ESOP from earlier and the investor wants another 15%, that's 25% of your company allocated to options. Make sure you actually need that many options - don't agree to a larger pool than your hiring plan requires.

Maintaining your cap table over time

A cap table is not a "set and forget" document. It changes every time you: - Issue shares or options to an employee - Grant equity to an advisor - Sign a new SAFE or convertible note - Complete a priced round - An employee leaves and their unvested options are returned to the pool

Update it immediately when any of these events happen. The biggest cap table disasters I've seen come from founders who didn't update for 18 months and then tried to reconstruct the history during a fundraise. Key documents were missing, option grant dates were uncertain, and the whole thing became a forensic accounting exercise.

Tips for keeping it clean:

1. Record every equity event. Date, type, number of shares, price, vesting schedule. Keep the source documents (board resolutions, option agreements, SAFE notes).

2. Review quarterly. At minimum, look at your cap table every quarter. Confirm it matches your corporate records.

3. Include fully diluted numbers. Your cap table should show both the current ownership (issued shares only) and the fully diluted ownership (including all options, SAFEs, and convertible notes as if they'd all converted or been exercised).

4. Get your lawyer to verify annually. Once a year, have your corporate lawyer confirm the cap table matches the company's share registry and corporate records.

Cap table red flags

These are the warning signs that your cap table is headed for trouble:

Founder ownership below 50% before Series A. If you've given away too much equity to advisors, early employees, and SAFE investors before your first priced round, you'll have very little room to manoeuvre. Investors want founders with enough ownership to stay motivated.

Too many SAFEs at different caps. Three or four SAFEs with different valuation caps and different terms creates a conversion nightmare. Keep your terms consistent whenever possible.

Advisor equity that's too generous. 0.25-0.5% for an advisor who helps occasionally is reasonable. 2-3% for someone who shows up to a monthly call is way too much. Be stingy with advisor equity - it adds up fast.

No ESOP or an undersized one. If you haven't reserved shares for employees, every future hire will dilute you and your investors. Set up the ESOP early so the dilution is planned, not reactive.

Missing paperwork. If you can't produce the signed option agreement for every equity holder, you have a legal problem. Fix this before you fundraise, not during.

Tools and recommendations

Early stage (pre-seed, 1-2 founders, no investors yet): A Google Sheet is fine. Three columns: name, shares, percentage. Update it when anything changes.

After your first SAFE or option grants: Switch to a proper tool. In Australia, Cake Equity is purpose-built for this and handles Australian corporate structures well. Internationally, Carta is the industry standard.

These tools do several things a spreadsheet can't: - Model SAFE and convertible note conversion automatically - Generate 409A valuations (relevant if you have US employees) - Manage option grants and vesting schedules - Produce investor-ready cap table reports - Maintain a legal record of all equity transactions

The cost is worth it. A cap table tool might cost $1-5K per year. A cap table error during a fundraise can cost you weeks of delays, thousands in legal fees, and potentially a worse deal because the investor lost confidence in your operational rigour.

And yes, you can use AI as a sanity check. Plug your terms into Claude, describe your cap table scenario, and ask it to model the conversion. Use it as a second opinion alongside your tool and your lawyer - not as a replacement for either.

The bottom line

Your cap table is the financial backbone of your company. It determines who owns what, and every future negotiation - fundraise, acquisition, employee offer - starts with it.

Build it on Day 1. Keep it updated. Use a proper tool once you have SAFEs or option grants. Model your SAFE conversions before the priced round, not during it. And read the documents carefully - pre-money vs post-money is not a minor detail.

The founders who get this right are the ones who walk into investor meetings with confidence. They know exactly what they own, what they'll own after the round, and what the cap table looks like in every scenario. That's the kind of operational discipline that makes investors say yes.

The founders who get it wrong? They find out at the worst possible moment - when the lawyers are building the conversion schedule and the numbers don't add up. Don't be that founder. Build the spreadsheet, use the tool, and know your numbers.