Building
The audit trail is the signature.
NumoForms has a signature question type: the respondent either types their name or draws a mark. What is stored is the whole audit record — the mark, whether it was typed or drawn, the exact agreement text that was on screen, a SHA-256 hash of that text, an ISO 8601 timestamp and the user agent. This is a simple electronic signature under the Electronic Communications Act 2000 and UK eIDAS. It is not a qualified electronic signature.
Why the mark is the least important part
A scanned squiggle proves very little. It can be lifted from one document and pasted into another, and nothing about the image says which document it was made against. What gives a simple electronic signature weight is evidence of a deliberate act: this person was shown this wording, at this time, and signed it.
So the question stores the wording itself rather than a reference to it. The agreement text travels with the response, and the record still reads correctly if the survey is later edited, reworded or archived.
Alongside the text sits a SHA-256 hash of that same text. Re-hash the stored wording, compare it with the stored hash, and a match means the wording is byte-for-byte what was presented. A mismatch means it was altered after signing. Changing one character, a "not" or a figure or a date, produces a completely different hash. That is what the hash is for. It is computed in the browser with the Web Crypto API, which needs a secure connection; signing pages are served over HTTPS, so in normal use it is always there.
What is stored with every signature
| Field | What it holds |
|---|---|
| The mark | The name as it was typed, or an SVG path if it was drawn. A path, not a picture. |
| Method | Whether the respondent typed the signature or drew it. |
| Agreement text | The exact wording shown above the signing area, stored verbatim so the record reads on its own without the survey. |
| Document hash | A SHA-256 hash of that wording, hex encoded. |
| Signed at | An ISO 8601 timestamp taken at the moment of signing. |
| User agent | The browser and device string, stored to the first 300 characters. |
The signing timestamp comes from the respondent's device; the response itself is timestamped by the database when it arrives. Two clocks on the record rather than one.
Typed or drawn
Type it
A single field for a full name, rendered in a script face. Faster on a phone, usable with a keyboard alone, and still legible six months later, which a mark drawn on a trackpad often is not.
Draw it
A drawing area handled with pointer events, so a mouse, a finger and a stylus all take the same code path, plus a clear control for starting again. The respondent picks the method, and which one they used is recorded.
A drawn mark is a path, not a picture
The obvious way to keep a drawn signature is a PNG data URL. NumoForms stores the stroke as an SVG path instead: a string of coordinates rather than an encoded bitmap. A fraction of the bytes in a response row, and it scales to any size without going soft at the edges. What leaves the product is the record rather than a rendered mark — see the limits below.
Where a simple electronic signature is enough
Under the Electronic Communications Act 2000 and UK eIDAS, a simple electronic signature is admissible for most agreements and needs no trust service provider behind it. That covers much of the paperwork forms already carry:
- Consent forms, including research and photography consent.
- School permission slips and trip authorisations.
- Ordinary contracts and service agreements.
- Declarations of accuracy on a grant or funding return.
- Sign-off that a policy or code of conduct has been read.
Where it is not enough
A qualified electronic signature is a different instrument: a certificate from a trust service provider, issued against a verified identity, created on a qualified device. We are not a trust service provider and nothing here is equivalent to one. If your process demands QES, you need a different product, and any vendor implying otherwise is worth a second look.
Nor does a simple signature verify identity: it records what was agreed and when, not who was holding the device. The rest of the limits are worth stating plainly:
- No certificate, no trust service provider, no qualified signatures.
- No identity verification, and no witness or countersigning step. One respondent signs one response.
- An existing document cannot be uploaded to be signed. The wording lives in the question, written per question rather than per survey.
- Nothing is emailed to the signer. The record stays with the response, and a CSV export carries the audit fields as data rather than a picture of the mark.
This page describes what the product records. It is not legal advice, and whether a simple electronic signature suits a particular agreement is a judgement for you or your legal team.
How it fits the rest of the survey
Signature sits in the Advanced group of the builder palette, next to file upload and address, and takes the same settings as every other question type. It can be marked required, it can sit behind conditional logic so only the relevant branch is asked to sign, and its agreement wording is written per question rather than per survey.
A signed response can then go through single-step approvals, where the decision and its timestamp are written by the database rather than supplied by the client. Audit record and approval record are kept the same way, for the same reason.
The record lives in the response row, in the same UK-hosted database as everything else, under row-level security with organisation isolation pinned server-side. See the security page.
Questions people ask about electronic signatures
Is a typed name a valid electronic signature in the UK?
The Electronic Communications Act 2000 makes an electronic signature admissible in evidence, and UK eIDAS confirms that a signature is not denied legal effect merely because it is electronic. Simple electronic signatures are used routinely for consent forms, permission slips, declarations and ordinary contracts. What is usually in question is not the format of the mark but whether you can show what was agreed and when.
Is this a qualified electronic signature?
No. A qualified electronic signature requires a certificate issued by a trust service provider, tied to a verified identity, on a qualified signature creation device. NumoForms is not a trust service provider and does not issue QES. If your process requires a qualified signature, you need a different product.
What happens if the agreement wording is edited after people have signed?
Nothing changes in the records already collected. Each signature carries its own copy of the wording and its own hash, so earlier signatures still show the text those people actually saw, while signatures collected after the edit carry the new text and a different hash.
Does an electronic signature prove who signed?
No, and no simple electronic signature does. It records a deliberate act, the wording that act applied to, the time and the device, but it does not verify identity. If identity matters, collect it alongside the signature with an email or address question, or pass a known identifier in through a hidden field.
Can a signature question be made mandatory?
Yes. A signature question takes the same required flag as any other question, so the survey will not submit without it, and it can sit behind conditional logic so it is only asked for on the branches where it applies.
Add a signature to your form.
Drop a signature question into any survey and the respondent types their name or draws a mark. Stored with it is the record that gives it weight: the exact wording they agreed to, a SHA-256 hash of that wording, the method, the time and the device.
- Typed or drawn, the respondent chooses
- Agreement text stored verbatim and hashed
- Simple electronic signatures, not qualified ones
