“The image is too big to send”
Pick “Images” or search directly and you get three steps: compress to a target size → resize → change the format; in most cases the first step is enough on its own.
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Guide
toolun has more than two hundred tools, but nobody opens it thinking “I want to use PDF Merge” — they think “I need to send this contract to the other side, so it has to be merged, page-numbered, watermarked and given a password”. Find a tool by task lists that kind of single job — 37 of them, covering office documents, images, audio and video, development and everyday life — gives each one a one-line goal, and then lays out 3–4 steps, every step linking to a concrete tool on this site and saying which parameters to choose and where the traps are.
Updated 2026-09-092 sources9 min read
toolun has more than two hundred tools, but nobody opens it thinking “I want to use PDF Merge” — they think “I need to send this contract to the other side, so it has to be merged, page-numbered, watermarked and given a password”. Find a tool by task lists that kind of single job — 37 of them, covering office documents, images, audio and video, development and everyday life — gives each one a one-line goal, and then lays out 3–4 steps, every step linking to a concrete tool on this site and saying which parameters to choose and where the traps are.
Two things it is not. It is not an outbound link directory, because every step happens inside toolun, so each one is “click and do it”. And it is not a tool manual: each tool page documents itself, and this page only says what the tool is responsible for inside this chain and how to set it. The “I have a file…” control at the top filters by file type: if you are holding a pile of HEIC files, you only see tasks that can start from HEIC; with no file at all, you see the “from scratch” tasks.
The list grew out of a product audit of searches that returned nothing: “image is too big to send”, “how do I turn a scan into a searchable PDF”, “video is too big for WeChat” — questions that no tool name can match, and exactly what this page exists to catch.
One of the tasks shown after picking “HEIC (iPhone photos)”:
Searching “contract”:
Images › A batch of HEIC → JPG → uniform size → long image
Goal: turn a set of iPhone photos into one long image you can post to WeChat Moments / Xiaohongshu.
1 Image Converter HEIC to JPG in bulk quality around 85 balances size and looks
2 Resize Images uniform width scale to "width 1080", height automatic
3 Long Image Stitch vertical join spacing and background colour optional
4 Image Compress fit the platform limit Xiaohongshu caps one image at 20 MB, WeChat long images are best under 5 MB
Note: when a long image gets very tall some platforms blur it, so split into two beyond 20 photosOffice documents › Contract: merge → page numbers → watermark → encrypt
Word to PDF → PDF Merge → PDF Page Numbers → PDF Watermark → PDF Protect
Office documents › Scanned pages → searchable PDF
Image Converter → Scan Enhance → Image to PDF → PDF OCR
Office documents › Sign a PDF and flatten it
Handwritten Signature → PDF Sign → PDF FlattenThe default shape of a tool site is a catalogue: every tool listed by category, and the user assembles the flow. That works for someone who knows the tool's name, and fails three other kinds of visitor — the one holding a file and unsure which tool fits, the one who knows the job but calls it something else (“remove the background” = cutout, “Apple photos” = HEIC), and the one whose job spans two or three tools. The audit found that searches from all three groups came back empty almost every time. A task page makes the job the entry point: every task is a fixed sequence of tools, and the user needs to know no tool names and to work out no order.
The principle is cut losses first, then process, then shrink. Take “scanned pages → searchable PDF”: convert the format first (many downstream tools cannot read HEIC), then enhance the image (deskewing and shadow removal raise OCR accuracy noticeably, so enhancement has to come before OCR), then assemble the PDF (running OCR over one PDF in a single pass is less work than image by image), and run OCR last. Compression always sits at the very end — it is lossy, and further processing after it magnifies the loss; encryption also comes last, because most tools cannot open an encrypted file. In the signing chain, “flatten” follows the signature, because flattening freezes editable objects into page content that can no longer be changed.
A yellow box flags three kinds of thing: irreversible (redaction, flattening, compression) — keep the original before you run them; legally loaded (an image signature is not the same as a certificate-based digital signature, and an official ID photo has to be taken at a designated studio); and platform rules (WeChat 25 MB, Xiaohongshu (RedNote) 20 MB, a 200 KB application portal) — these are why the task exists, and they decide the parameters of the last step.
The advice on each step is the value that has proved most reliable in that chain, not the only correct one: JPEG quality 85 is the usual turning point between size and looks; a long image 1080 px wide matches the CSS pixel density of mainstream phones; 720p at 1.5 Mbps is the combination that fits two minutes inside 25 MB; a watermark opacity of 15–25% stays visible without covering the body text. Every number can be adjusted on the individual tool page, whose notes explain the reasoning in more detail.
This page is the master index of tasks; each task will later get a flow page of its own (/guide/<slug>) carrying a longer background and screenshots, and a task's id here is the slug of that future page. The task chips in the site-wide search will link to the matching anchor here (#task-<id>), so whichever entrance you come through you land on the same chain.
Pick “Images” or search directly and you get three steps: compress to a target size → resize → change the format; in most cases the first step is enough on its own.
The second task in “Office documents”: Word to PDF → merge → page numbers → watermark → encrypt, with a warning box reminding you to keep an unencrypted copy and send the password through another channel.
“I have a file → HEIC” narrows the list to a few entries, and the first is convert → uniform width → stitch → compress.
The “Development” group: the recipe from the Git cheat sheet + gitignore / licence choice from the developer directory + a mock terminal to rehearse in.
At the moment, yes. The file only ever travels between your browser and your local disk, never through a server; direct hand-off between tools is being built, and once it ships the tasks here become continuous flows.
Because extra steps can cost you (one more compression, one more transcode). A chain is only as long as the minimum set of steps needed to reach the goal.
Try search first (step notes and tags are matched too); if it still comes up empty, use the site-wide search to find a single tool or browse the relevant category. The task list is extended in batches from records of searches that returned nothing.
No. They are the safest values for common cases and can be adjusted on the tool page, whose notes explain the reasoning behind each parameter.
This page is navigation only: the task data loads statically with the page, and search, filtering and bookmarks happen locally in the browser without sending a request. Every tool it links to processes files in the browser (the few marked API call a third-party interface and say so), intermediate results sit in your download folder, and this site's servers never receive a file.
Updated 2026-09-09
37 common in-site workflows for tasks such as searchable scanned PDFs, contract merging and encryption, HEIC conversion, video compression, social covers, and ID photo backgrounds, with 3–4 linked steps each
Pick a file type to show only the tasks that can start from it. Each task is a one-line goal plus 3–4 steps, and every step links to a specific tool with the settings explained; passing files between tools still means downloading and uploading for now (file dock hand-off is on the main roadmap).
Turn phone photos of a contract or book pages into a PDF you can search and copy text from.
iPhone photos default to HEIC, which many downstream tools cannot read; skip this if they are already JPG/PNG
Auto-crop, deskew, remove shadows and boost contrast; OCR accuracy improves noticeably
Drag them into page order; pick A4 so every page is the same size
Produces a PDF with a hidden text layer: the look is unchanged, but text becomes searchable and copyable
Combine a body and its attachments into one PDF with page numbers, a watermark and an open password, and send it out.
Skip if everything is already PDF
The list order is the final page order; drag to adjust
"Page X / Y" centred in the footer; the cover can start numbering from page 2
Text watermark reading "For XX review only" plus the date, at 15–25% opacity
Send the open password through another channel; a permissions password can block printing and copying
Compress a tens-of-MB PDF down under the attachment limit (usually 10–25 MB).
Try "Medium" first; scanned PDFs usually shrink by 60–80%
Send it as two or three parts, or split by chapter
ZIP barely shrinks an already-compressed PDF; it is mainly for bundling
You have a PDF report or table and need to change its content.
If text can be extracted it is a "native PDF" and converts well; if extraction is empty it is a scan
Give it a text layer
Use this for documents; complex layouts may need manual touch-ups
Use this for tables; it detects the table structure page by page
Sign a PDF you received and send it back so the signature can no longer be changed.
Draw with a mouse or touchscreen and export a transparent PNG
You can add a date and text at the same time
Bakes the signature and form fields into the page content so they cannot be moved or deleted
Hide ID numbers, amounts and names before sending, so they cannot be recovered.
Select a region and the tool deletes its text and images rather than painting black over them
Author, title and creating application can leak information too
Extract the full text and confirm the redacted content is really gone
Hand it to a print shop or a reader without the layout shifting.
Use landscape for wide sheets; set the print area in Excel first
Two or four handout pages per sheet
Hand a Markdown document to someone who does not use Markdown.
Check heading levels and code blocks
Pick a theme and paper size
Pasting the HTML into Word keeps headings and lists
Dozens of files like "scan001.pdf" renamed to date-client-type.
Sequences, dates, find-and-replace and case changes; preview before running
Find repeated files by content hash
Turn a set of iPhone photos into one long image you can post to WeChat Moments or Xiaohongshu.
Quality around 85 balances size and sharpness
Scale to a width of 1080; height follows automatically
Spacing and a background colour can be added
Xiaohongshu allows 20 MB per image; keep WeChat long images under 5 MB
WeChat, email or an upload form says the image is over the limit.
Set a target size (say 2 MB) and let the tool find the quality setting
1080–1440 px wide is plenty on a phone screen
Converting a PNG screenshot to JPG or WebP usually halves it or better
Turn a phone selfie into a 1-inch or 2-inch ID photo on a white or blue background.
The model runs in the browser and the photo is never uploaded
Pick 1-inch, 2-inch or an exam spec and a background colour; a print sheet is laid out automatically
Many application systems cap files at 20–200 KB
Produce a 900×383 header plus a 500×500 thumbnail that survives sharing to Moments.
Keep the title in the middle third: Moments only shows the centre 1:1
Or use the "WeChat header" preset in the social size export
Use at least 60 px so it stays legible on a phone
One image produces both 900×383 and 500×500
Put a consistent credit on client proofs and work posted online.
Text or logo, tiled or in a corner, around 30% opacity
Clear GPS location and device details before publishing
Turn several chat or UI screenshots into one image safe to post publicly.
Avatars, names, phone numbers; mosaic is harder to reverse than blur
The easy option for group photos
Rounded corners make a screenshot look more like a card
Slice an image into nine tiles and post them in order.
The grid only shows squares
3×1 and 2×3 are also available
Remove scratches, colourise and enlarge a scanned old photo.
Deskew and remove shadows first
Local models for repair and colourisation
Final colour grading and sharpening
One logo in, favicon, Apple Touch Icon and PWA icons out.
Leave 15% margin so a circular mask does not clip the subject
Outputs 16 / 32 / 180 / 192 / 512 plus the manifest snippet
Fit within WeChat's 25 MB per file (chats) or 5 minutes (Moments).
Resolution, bitrate and duration decide how to compress
Half the duration means half the size
Choose target size 25 MB, or 720p at 1.5 Mbps
Grab a few seconds of video and turn it into a GIF for chat.
Remove black bars and focus on the subject
320–480 px wide at 10–15 fps keeps the size manageable
WeChat stickers must stay under 1 MB
You only need the sound from a lecture or interview video.
Choose MP3, or copy the stream losslessly as AAC
When the background noise is heavy
Bring mismatched segments to -16 LUFS
Combine a few phone-shot clips into a single video.
Mixing landscape and portrait produces black bars
Lossless when the parameters match, otherwise re-encoded
So the cuts do not feel abrupt
The downloaded SRT does not line up with the video, or the player only reads another format.
SRT / VTT / ASS conversion, shifted earlier or later by N seconds
GBK subtitles break on Mac and phones; convert to UTF-8
Record a voice-over or memo and remove noise and silence.
You have a response and need to make sense of the status code, JSON structure and token contents.
4xx is a request problem, 5xx is server-side; the cards include handling advice
Errors point to line and column; unescape strings that were encoded twice
Check whether exp has passed and what the payload holds
Turn the Unix timestamps in the response into readable time
Find where a production config differs from the local one.
Convert YAML and JSON to the same format when they are mixed
Differences only mean something once indentation and key order match
Highlighted side by side
The server backs up every night; make sure the expression is right.
Enter it and check the next 10 run times
The crontab entry in the "processes and services" group has a complete example
755 lets cron execute it
Convert a long docker run command into an easy-to-maintain compose.yaml.
Unrecognised flags are flagged explicitly
systemctl enable docker、usermod -aG docker
Split 10.0.0.0/16 across several departments.
Enter a CIDR to see the host range and split it as needed
ip addr、ip route、ss、nc
Turn locally written code into a remote repository.
Five steps: init → add → commit → remote add → push -u
gitignore.io and Choose a License live in the "Git & collaboration" group
Push in the simulator before doing it for real
Turn a link, Wi-Fi network or contact card into a QR code for a poster.
A Wi-Fi QR code connects on scan; pick error correction H if you add a logo
Check with a phone or this tool before printing
Use SVG or a PNG of 1000 px or more for print
Create a password when signing up and read TOTP codes locally.
16+ characters including symbols
The secret is never stored; a stand-in for an authenticator app
Inches to centimetres, pounds to kilograms and currency conversion.
Length, weight, temperature, area
Needs a network connection for rates