API comparison · 25¢ per envelope · No monthly fee
Start with 25 free sandbox envelopes, no card and no licence to assign. After that, 25¢ per envelope with no seats and no minimum, sent by email and text in one call.
You get a sandbox key on the next screen. Real delivery, not a simulation.
Check your email
We sent a sign-in link to . It is good for 15 minutes, and your sandbox key is waiting on the other side.
| Siglio | Adobe Acrobat Sign | |
|---|---|---|
| Price per envelope | 25¢ | Not published |
| Monthly fee | $0 | Not published for the tiers that carry API access |
| Per-seat fee | $0 | US$16.99, US$23.99 and US$29.99 per licence per month on the published business plans (annual, billed monthly) |
| Minimum commitment | $0 | Not published |
| SMS delivery | Included at the same 25¢ | Not published |
| Sandbox access | Key on screen in about a minute. No card, no account review. | “Register a Developer account”; the terms are not published |
| Webhook on every event | Every event type, every account | “Webhooks are supported in the REST API v6 and later”; the plans that carry them are not stated |
| Multi-signer | Two per envelope, signed in order | Not published |
Adobe figures are quoted from Adobe's published Acrobat for business plans page and its Acrobat Sign API FAQ, checked on 14 September 2026. The per-licence prices are from the business plans page; the API FAQ states that “API access is reserved exclusively for enterprise and developer tier accounts”, and the price of those tiers is not published. So the published seat prices and the tiers that carry API access are not the same thing, and the table says so rather than implying one price covers both. A cell reading “Not published” is not stated on either page. Prices change; check the source before relying on it.
The thing worth noticing is that the prices Adobe publishes and the tier that carries API access are not the same thing. The per-licence prices above are the business plans; the API FAQ says access is reserved for enterprise and developer tier accounts, and those are not priced on the page. If you need Acrobat itself, none of that is a criticism, it is just a different purchase from an API key.
A bearer token, one POST and one webhook. No licence to assign to anybody and nothing to install.
Put ^S1 where the signature goes and ^D1 where the date goes, in white text. Invisible to the reader, findable by us.
One JSON request with the file and the signer. Delivery by email, text or both starts immediately.
envelope.completed lands on your endpoint with a link to the signed PDF and its certificate.
| What | Siglio |
|---|---|
| Per envelope | 25¢ |
| Monthly fee | $0 |
| Per seat | $0 |
| Minimum | $0 |
| SMS delivery | Included, same 25¢ |
| Sandbox | 25 envelopes free, no card |
You are billed when an envelope is created, not when it is signed. A declined or ignored envelope still costs 25¢.
Because Adobe does not publish one on the pages linked under the table. The business plans page prices licences; the API FAQ says API access is reserved for enterprise and developer tier accounts and does not price them. We are not going to estimate a number and put their name next to it.
Everything around the document rather than the send: Acrobat itself, PDF editing, enterprise identity and provisioning, government and regulated-industry compliance programmes, and integration into a suite most large companies already own. If your organisation runs on Adobe, that gravity is real and this page is not going to move it.
Software that needs to send a document for signature and get it back signed, at a published 25¢ with no licence to assign to anyone, including signers on a phone who get it by text instead of email.
Electronic signatures have carried the same legal force as ink in the United States since 2000 under the federal ESIGN Act, and at state level under UETA. What survives a challenge is the record behind the signature, so every completed envelope carries a certificate page with the timestamp and IP address of each event. For a use case near an edge, ask your own counsel rather than any vendor page, ours included.
Both source links under the table go to Adobe’s own pages, dated the day we read them. Read them before you rely on anything here, and if something has changed or we have it wrong, tell support and we will fix the page.
25 free envelopes, no card, no call. The key is on the next screen.
You get a sandbox key on the next screen. Real delivery, not a simulation.
Check your email
We sent a sign-in link to . It is good for 15 minutes, and your sandbox key is waiting on the other side.
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