The first question almost every founder asks us is "how is this different from Carta?" The honest answer is: Carta is excellent at being Carta, and we are not trying to be Carta. We think most founders will use both products, just not at the same time. Here's what we mean.

What Carta is, accurately.

Carta is the system of record for equity at companies that have one. It was built for, and refined around, the needs of growth-stage and late-stage companies: multiple share classes, secondary transactions, 409A valuations, exercises, tender offers, audited cap-table history, ASC 718 reporting, in-house and outside counsel involvement, and a procurement process that takes weeks.

At that life stage, Carta is genuinely excellent. The cap table is the source of truth for an enormous amount of legal and financial machinery, and Carta's product surface reflects that — it is precise, slow, and built to be operated by people whose job title is "stock plan administrator."

What Carta isn't built for.

Carta is not built for the early years. It can be used in the early years — millions of companies do — but the experience is mismatched in a few specific ways:

  • It's expensive at small scale. Roughly $240/month for a startup with under 25 stakeholders, last we checked. For a seed company on a $1.5M annual budget, $3K/year for cap-table-only software is real money.
  • It assumes you have counsel. Many flows nudge you toward, or assume, a relationship with outside counsel. At seed, most founders don't have that yet.
  • It does the cap table only. Your deck, your investor pipeline, your data room, your forecast and your updates are someone else's problem — DocSend, Notion, Carta itself for some data-room features, Causal or Excel, and Mailchimp respectively.
  • It is not opinionated about the round. It will store the SAFE you upload. It will not tell you whether the SAFE you uploaded is the post-money or pre-money template, whether the MFN clause matters here, or whether your dilution is in the normal range.

Carta is a stock-administration system. Arx is a fundraising operating system. The difference matters.

What Arx is.

Arx is the workspace for the years between zero and Series A. It contains a cap table — a real one, with SAFEs and convertibles and an options pool and a pro-forma engine — but the cap table is only one of ten surfaces. The other nine are the rest of fundraising: investor pipeline, deck analytics, data room, updates, calendar bookings, the forecast and benchmarks panel, the AI assistant, integrations, and the resource library.

Where Carta is built for the day-to-day administration of equity at a mature company, Arx is built for the actual job of raising the next round at an early-stage one. The job is different. The tooling is different.

One way to think about it. Carta is what your COO uses to administer the equity you already raised. Arx is what your founders use to raise the next dollar of it.

Where the overlap actually is.

The overlap is real, and we should name it honestly. Arx and Carta both have:

  • A cap-table ledger.
  • SAFE management.
  • A data room (Carta has one through Carta X).
  • Stockholder views and consent tooling.

We do not think we are better than Carta at any of these in isolation. We do think we are better than Carta + Notion + DocSend + Calendly + Causal + Mailchimp in aggregate — because we don't treat the round as five workflows; we treat it as one workflow with five tools woven through it. The cap table updates feed the pipeline. The pipeline feeds the updates. The updates feed the benchmarks. The benchmarks feed the model. Nothing is duplicated by hand.

The graduation moment.

What happens when you outgrow Arx?

For most companies, the right answer is to move the cap-table-of-record to Carta around the time you do your Series A. By then you have multiple share classes, a 409A on the way, real option-grant volume, outside counsel, and stock-plan administration that benefits from Carta's depth. We will export your cap table cleanly. We expect to lose the cap-table-of-record relationship at that life stage. We are fine with that.

You will likely keep using Arx after Series A — for investor updates, for the pipeline that becomes your B round, for deck analytics, for the forecast — but the cap table will sit in Carta. That's the natural arrangement.

Pricing, briefly.

Arx is $99/month, all-in, unlimited seats, billed through Stripe with no sales call. Carta is roughly $240/month for a small startup, and meaningfully more once you add features and stakeholders. We are not trying to undercut Carta; we are trying to be priced for the life stage we serve.

A founder who needs only a cap table — no pipeline, no updates, no deck analytics, no forecast — is probably better off on a cheaper cap-table-only product, of which several exist. A founder who is running a round across six surfaces is the one we're built for.

The honest comparison table.

We dislike comparison tables that grade competitors on dimensions they didn't optimize for. Carta is not bad at the things we do — it didn't try to do them. Arx is not bad at 409A workflows — we didn't try to do them. Here's the honest version:

  • Cap table depth at scale. Carta wins. Materially.
  • 409A, ASC 718, secondary, tender offers. Carta wins by default — we don't offer them.
  • Cap-table pro-forma for a seed priced round. Comparable. We're easier to learn; Carta is more battle-tested.
  • Investor pipeline / CRM / intro paths. Arx. Carta has no equivalent.
  • Deck analytics. Arx. Carta has no equivalent.
  • Investor updates. Arx. Carta has no equivalent.
  • Forecast and benchmarks. Arx. Carta has no equivalent.
  • Bookings. Arx. Carta has no equivalent.
  • AI assistant that reads your private data. Arx.
  • Price for an early-stage company. Arx, by roughly 2.5×.

The summary.

Carta is the right answer once your company is mature enough to need the depth Carta is uniquely built for. Arx is the right answer for the years before that — when the job is not administering equity but raising it. We don't think you have to pick between us; we think the natural arc is Arx, then Arx and Carta.

If you're running a seed today and you're paying $240/month for a Carta plan that's storing one Common share-class entry and four SAFEs, you might want to look at us. If you're running a Series B with a 409A in motion, you should stay on Carta — and we'd happily be the deck-and-pipeline layer alongside it.