Signing

Nixt PDF signs documents in two different ways, and it matters which one you need:

Both are on the Fill & Sign tab, in the Sign group. Sign is on the Home tab too.

Making your signature or initials

The first time you use Sign or Initials, Nixt PDF asks you to make one. You can also click Make one… in the tool strip, or New signature… in the list of your signatures.

The dialog is titled Your signature or Your initials.

1. At the top left, choose Signature or Initials.
2. At the top right, choose the ink: black, blue or red.
3. Choose how to make it — Draw, Type or Picture — and follow the steps below.
4. Leave Keep it on this computer to use again. It is never sent anywhere. ticked to save it, or untick it to use it this once.
5. Click Use it. It’s dimmed until there is something to use.

Draw

Draw your signature in the box that says Sign here, with a mouse, a trackpad or a stylus. A stylus’s pressure, or the speed of a mouse, varies the line’s thickness, and the result is kept as smooth curves, so it stays sharp at any zoom.

• Pen — the slider sets how thick the line is.
• Undo stroke — takes off the last stroke.
• Clear — starts again.

Type

1. Type your name in Your name, or your initials in Your initials. It starts with the name or initials from Your details. Names can be up to 60 characters and initials up to 8.
2. Click one of the handwriting styles shown: Formal, Flowing or Casual.

A name in letters the handwriting styles don’t have — Cyrillic, Greek, Arabic or Chinese, for example — is written in your computer’s own lettering as a picture instead, and the dialog says so.

Picture

Use a photograph or a scan of your signature on paper.

1. Click Choose a picture… and choose the picture.
2. Take the paper away is ticked, so the paper is removed and the signature sits on the line rather than in a grey box. Drag Keep lighter strokes until faint parts of the signature are kept but the paper isn’t.
3. Tick Use the ink colour above to recolour the signature in the chosen ink.

Choosing among saved signatures

Your saved signatures and initials are kept on this computer, up to 24 of each. When you save a 25th, the oldest of that kind is removed.

1. With the Sign or Initials tool in use, click the picture of your signature under Yours: in the tool strip.
2. In the Your signatures (or Your initials) dialog, click the one to use. The one in use is outlined.

To delete one, click the bin beside it (Forget this one). To make another, click New signature… or New initials….

Putting your signature or initials on the page

1. On the Fill & Sign tab, click Sign or Initials.
2. Put it down:
   • Click to place it at its natural size, centred where you click. An outline under the pointer shows its size.
   • Drag a box to fit it into the box.
   • Click an empty signature field — outlined in amber — to fit it into the field.

When it goes into a signature field, the message reminds you: This is a picture of your signature, not a digital one — the Digital ID option signs it for real.

Initials on every page

With Initials chosen, turn on On every page in the tool strip before you place them. They go on every page at the same place relative to the page — the corner of each page of a contract, for example. It’s one step for Undo.

Moving, resizing and fixing

With the Sign tool in use, press a signature or initials to pick it up. Move, resize, nudge and delete it the same way as a stamp — see Working with a stamp on the page. The action bar offers Fix to page and Delete.

A signature placed this way is a comment, which any PDF reader can move or delete. Fix to page makes it part of the page. See Fixing stamps to the page.

Signing with a digital ID

A digital signature records who signed, using the certificate in your digital ID, and seals the document so that any change afterwards can be detected. You need a digital ID — a .p12 or .pfx file — and its password. Your organisation or a certificate authority can issue one, or you can make a self-signed one; see Digital IDs.

Choose where the signature goes

1. On the Fill & Sign tab, click Digital ID.
2. Choose a place:
   • Click an empty signature field (outlined in amber) to sign in that field.
   • Drag a box where the signature should appear.
   • Click an empty part of the page for a box of standard size centred there.

To sign without choosing a place first, choose More › Sign with a digital ID….

Open your digital ID

The Sign with a digital ID dialog opens.

1. Click Choose the file… and choose your .p12 or .pfx file.
2. Type its password in Its password.
3. Click Open it, or press Enter. It reads Opening… while it works.

If the file doesn’t open, the reason is shown in red; see Digital IDs.

Once it opens, the dialog shows whose certificate it is:

• The name, organisation and country in the certificate, such as Alex Morgan, Example Ltd, GB.
• Who issued it and until when, such as Self-signed · valid until 14 September 2031 at 10:00, or Issued by followed by the issuer.
• The kind of key, such as RSA 2048, and the start of the certificate’s fingerprint.
• Warnings, when they apply:
  • It expired on followed by the date, and A signature made with it will not check as valid.
  • It is not valid until followed by the date.
  • Its certificate does not allow signing documents.
  • It is self-signed: people you send the document to will see who it says, and will have to decide whether to trust it.
• Everything it says… — opens the full certificate.

Set up the signature

The reason, place, contact details and timestamp server are remembered for next time.

Sign

Click Sign (or Certify). It reads Signing… while it works, and is dimmed when In the signature field is chosen with no field selected.

The message says, for example, Signed as Alex Morgan. Save to keep the signature — Nixt PDF did not keep your digital ID or its password.

A name, reason or place in any script is shown in a visible signature; the letters are drawn by your computer. If some couldn’t be drawn, the document isn’t signed rather than signed showing question marks.

When the signature goes into a field whose form locks other fields on signing, those fields are made read-only.

Certifying a document

A certifying signature says what may still happen to the document afterwards. Only the first signature on a document can certify it, so the Certify choices are offered only on a document with no signatures.

A document certified to allow no changes can’t be signed again.

Trusted timestamps

A signature’s time normally comes from your computer’s clock. A trusted timestamp is proof of the time from an independent timestamp authority, which people checking the signature can rely on.

• Timestamp server starts with a public timestamp authority’s address the first time. Replace it with the one your organisation uses, if it has one.
• Only a fingerprint of the signature is sent to the server, never the document.
• The reply is checked before anything is written. If a timestamp can’t be had, the document isn’t signed, and the reason is shown — see Troubleshooting.

This is the one feature of Nixt PDF that uses the network, and only when you tick it.

When a document isn’t signed

Related pages

• Digital IDs — making a digital ID, the files Nixt PDF reads, and trusted certificates.
• Validating signatures — checking the signatures on a document.