Compress a PDF to under 1MB
Get a PDF under 1 MB for email, without sending it through anyone's server.
Or drop one anywhere on this page
What to know about Compress PDF to 1MB
One megabyte is a comfortable target: most documents reach it while staying perfectly readable. This finds the mildest setting that fits, on your own device, and keeps the text layer intact so the file you send is still searchable at the other end.
One megabyte is a forgiving target, and that shapes what this page is for. Most documents reach it without visible damage, which makes it the right size to aim for when the constraint is an email or an upload form rather than a portal demanding something drastic.
The first thing worth knowing is that email lies to you about size. Attachments cannot travel as raw binary, so they are encoded into printable characters, and the classic encoding turns every three bytes into four — about 37 percent larger, before message headers. A 900 KB PDF reaches the mail server as roughly 1.2 MB, which is why an attachment comfortably under a limit on your disk is refused in transit. When the number came from a mail system rather than a web form, aim for around 70 percent of it.
The second is that the limit is enforced twice. Your own server decides whether the message may leave; the recipient's decides whether it may arrive. Gmail's 25 MB and Outlook's 20 MB are generous, but a corporate Exchange server is often set to 10 MB or less, and you cannot see that number from outside. A delivery failure hours after sending usually means you cleared the first check and failed the second. A document under 1 MB clears essentially all of them.
What happens here is a search. Compression offers two useful controls — how far images are downsampled, and how hard they are re-encoded — and rather than guessing, several combinations are tried and measured, and the gentlest one that meets your target is kept. At 1 MB that usually means photographs and charts survive at a sensible resolution, so the file your client opens still looks like the file you made.
Before any image is touched, a lossless pass runs alone: duplicated resources, unused objects and the redundancy that collects in a file that has been edited or merged. It changes nothing visible, and for a text-heavy report it is frequently enough by itself.
The text layer is left intact throughout, which matters more for email than for anything else. The person receiving your document can still search it, select from it and copy out of it. The single exception is the rasterise checkbox, off by default — it redraws every page as a picture, which reaches almost any size and destroys searchable text along the way. Most compressors do that silently whenever a preset promises a dramatic reduction. Here you decide, with the consequence written next to the box.
And the document never leaves your device. Contracts, offers and client reports are compressed in your own browser tab, with no upload, no account and no retention policy to go and read — which is also why it keeps working with the network switched off.
How to get a PDF under 1 MB for email
- 1
Add the PDF
Choose the file or drop it here. It is opened in this tab — a contract or report is never uploaded to be measured.
- 2
Set the target a little low
1 MB is filled in. If the limit is your mail server's rather than a web form's, try 700 KB — attachments grow by about a third in transit.
- 3
Run the search
Several settings are tried and the gentlest one that fits is kept, so charts and body text stay sharp.
- 4
Send it
The text layer survives, so the recipient can still search and copy from the document you sent.
What Compress PDF to 1MB accepts and produces
- Input
- One PDF. Reports, contracts, slide exports and scans all work.
- Output
- A PDF at or under 1 MB with its text layer intact, or the closest it reached and why.
- Limits
- Email encoding adds roughly a third to an attachment in transit, so a mail server enforcing 1 MB may reject a file that is 900 KB on disk. Aim below the stated limit when the limit belongs to a mail system.
- Offline
- Yes, entirely, after your first visit.
Why Compress PDF to 1MB here
- Contracts and reports never leave your device — no upload, no account, no retention policy to read
- Text stays selectable and searchable for whoever receives the file
- Keeps the mildest setting that fits, so charts and screenshots are not smeared
- Accounts for the fact that email inflates attachments in transit
- No watermark on a document going to a client
- Works with the network switched off once the page has loaded
Where your file goes
Nowhere. This tool runs inside your browser, and the page is served with a policy that forbids it from sending your document anywhere. You can confirm that yourself: open your browser’s developer tools, watch the Network tab, and process a file.
Questions
Why was my 900 KB attachment rejected by a 1 MB limit?
Because email cannot carry raw binary data. Attachments are encoded — historically with base64 — which represents every three bytes as four printable characters and inflates the file by about 37 percent before headers are added. A 900 KB PDF arrives at the mail server as roughly 1.2 MB. When the limit belongs to a mail system rather than a web upload form, aim for about 70 percent of the stated number and you will stop being surprised.
What are the real attachment limits?
Gmail accepts 25 MB and quietly converts anything larger into a Drive link. Outlook.com allows 20 MB, while a corporate Exchange server is frequently configured far lower, and 10 MB is common. The awkward part is that the limit is enforced at both ends: your message can leave successfully and still be refused by the recipient's server, which is where a bounce hours later comes from. Compressing to 1 MB puts you comfortably inside almost every configuration.
Should I compress it or send a link instead?
If the document must be readable in ten years, sitting in a mail archive, send the file — links expire, permissions get revoked, and the sharing account eventually closes. If it is a large deck being reviewed this week, a link is kinder to everyone's inbox. Compressing to 1 MB is the middle option that usually wins for anything contractual: small enough to send, self-contained enough to keep.
Will 1 MB still look professional?
In most cases yes, and this is the practical difference between this target and a much smaller one. At 1 MB there is normally enough room to keep photographs and charts at a sensible resolution, so the document a client opens looks like the document you made. The tool keeps the mildest setting that meets the target rather than the most aggressive available, which is what preserves that.
I need to attach several files under one limit.
The limit applies to the whole message, so five 1 MB attachments meet a 5 MB limit only before encoding, and after it they do not. Compress each one, add up the results, and leave about a third of the limit as headroom. Merging them into a single PDF first is often better anyway — one attachment cannot arrive partially, and the recipient does not have to keep five files together.
Does the compressed file stay searchable for the recipient?
Yes. Compression here works on the images inside the document and on redundant structure; the text layer, the embedded fonts and the layout are left alone, so the person receiving it can still search, select and copy. The one exception is the rasterise checkbox, which is off unless you tick it — that redraws pages as pictures and does destroy searchable text, which is exactly why it is not the default.