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Outils PDF, image, développeur, SEO, texte, étudiants et professionnels — tous gratuits, tous entièrement dans votre navigateur. Pas d’envoi, pas de compte, aucun serveur ne voit vos données.

No sign-up required No file size uploaded anywhere Works offline once loaded

The highest-demand tools with full options — browse by category below for the rest.

Each tool runs entirely with JavaScript already loaded in this page — PDF tools via pdf-lib and pdf.js, image tools via the browser's native Canvas API, and everything else with plain JavaScript. Your files or input are read into browser memory, processed, and handed back as a download or copyable result. This page itself is served by a small Laravel route; Laravel never sees your files either. The only backend in use is Supabase, and only for two optional things: signing in with a magic link, and — only if you're signed in — a log of which tool you ran and when. Honest limits worth knowing: Compress PDF flattens each page to a re-encoded image (great for scans, not ideal if you need selectable text after); HEIC conversion depends on your browser (Safari usually works; Chrome often cannot decode HEIC without a library we don't ship); Fill PDF Form is best-effort for simple AcroForm fields, not a full Adobe Forms replacement; and Word/Excel/PowerPoint ⇄ PDF genuinely needs a server-side engine, so it isn't included — this build only ships tools that can honestly run client-side.

Does it keep the image quality?

Resizing down generally looks sharp; resizing up beyond the original resolution will look softer, since no new detail can be invented — that's a limit of any resizer, not specific to this one.

What does "Lock aspect ratio" do?

Keeps width and height proportional automatically as you change one of them, so the image doesn't stretch or squash — uncheck it if you deliberately want a different aspect ratio.

What output format do I get?

The same format as your input — a PNG in stays a PNG out, a JPG stays a JPG, so transparency (if any) is preserved for PNGs.

Can I resize to a percentage instead of exact pixels?

Enter exact pixel dimensions — for a percentage, calculate the target pixel size yourself first (e.g. 50% of 1200px width is 600px) and enter that.

Is there a maximum size?

No hard limit enforced here — very large target dimensions are only limited by your device's available memory.

Does it crop anything?

No — resizing stretches or shrinks the whole image to the new dimensions; nothing is cut off. Use Image Cropper if you want to trim to a specific area instead.

Can I resize multiple images at once?

Not in one run — this works on one image at a time; run it again for additional images.

Is my image uploaded anywhere?

No — resizing happens entirely in your browser using the Canvas API; nothing is uploaded.

Is this really free, and is there a file size limit?

Yes — no account, no paywall. Since processing happens in your browser's memory rather than uploading anywhere, the practical limit is your device's available RAM, not a server quota. Very large files (500+ pages) may run slower, especially for Compress and PDF→JPG.

Does anything about my file get sent anywhere?

No. Every tool runs with pdf-lib/pdf.js loaded in this page; your file is read into browser memory and never leaves it. The only network call this app makes for your account is Supabase auth — and that only stores which tool you ran and when, never file content.

Why isn't Word/Excel/PowerPoint → PDF included?

Converting Office formats accurately needs a real rendering engine (what Word or LibreOffice use internally) — no browser library does this reliably. Rather than ship a broken version, it's left out.

Does TechDriven Tools have OCR (text recognition)?

Yes — OCR PDF recognizes text in scanned or photographed pages using Tesseract.js, running entirely on your device, and gives you a searchable PDF or a plain text file. Nothing is uploaded for this either.

Can I use this without an internet connection?

Once the page and its libraries have loaded once, yes — the tools themselves need no network access. Signing in and viewing history do require a connection, since those talk to Supabase.

What happens to the "history" if I sign in?

Only a row per tool run — the tool's name and a timestamp. No filename, no file content, ever. You can see the full list any time via the History button.

Are the non-PDF utilities (password generator, JSON formatter, etc.) private too?

Yes — same rule as the PDF tools. Word Counter, Case Converter, Password Generator, UUID Generator, Base64, Hash Generator, JSON Formatter and JWT Decoder all run with plain JavaScript already loaded in this page; nothing you type or paste is sent anywhere.

Image Resizer scales to exact dimensions or common presets for avatars, hero slots, and email widths without an editor install.

100% FreeRuns in Your BrowserNo Sign-upNo Upload

How Image Resizer works here

Image Resizer runs locally in your browser on TechDriven Tools. Inputs stay on your device — nothing is uploaded for this step.

Read every label before running. For Image Resizer, the controls that change outcomes most are: width/height or preset dimensions, optional aspect lock. Change one control at a time when you are comparing results.

When to use it

Use Image Resizer when the job matches what the tool is named for — not as a generic substitute for unrelated PDF or data tasks.

Prefer this browser version when the input is sensitive and you want processing to stay on-device with clear option names like: width/height or preset dimensions, optional aspect lock.

If the next step differs (for example you finished and now need a sibling utility), jump to a related tool instead of forcing one screen to do everything.

Teams standardize on Image Resizer when the alternative is emailing files to a consumer upload site. Document the preferred option defaults (for example the usual quality, corner, or rate) so everyone reproduces the same result.

If Image Resizer is only one step in a pipeline, write the order down: what happens before, what happens after, and which related tool owns each step. That prevents double-processing and accidental quality loss.

On mobile, prefer moderate file sizes and simpler option combinations. Local processing is powerful, but phones have less memory than desktops for huge scans or megapixel images.

Avatar uploads. Resize to the exact pixel box a form requires.

Email width limits. Scale screenshots to ~600px wide for predictable rendering.

Print vs screen. Create a smaller web derivative without overwriting the print master.

Options that change the result

Primary controls

The important controls are: width/height or preset dimensions, optional aspect lock. Change one at a time when comparing outcomes so you know what improved the result.

Run and verify

After you run Image Resizer, open or inspect the output on the device where you will share it. Keep originals until that check passes.

Boundaries

This page does not replace desktop suites for heavy Office conversion or certified legal e-sign. It covers the focused job described above.

Practical defaults

Start with conservative defaults on Image Resizer, run once, then adjust. Extreme settings (lowest quality, highest tip, densest QR payload) are for known constraints — not first tries.

Inputs that surprise people

People often misread units or page indexes. Align with the on-screen labels and the total page count or unit selectors before blaming the engine.

Outputs and naming

Rename downloads immediately (date + client + purpose). Image Resizer may use a generic filename; clear names prevent sending yesterday’s draft.

Accessibility and sharing

After visual tools (watermark/sign/page numbers), skim a page with fresh eyes for contrast and coverage. After data tools, copy results into the system of record your team actually uses.

Image Resizer options
Image Resizer result

Privacy

Image Resizer is designed to run in your browser so your files and text are not uploaded for the core transformation.

Still handle downloads carefully: a private process can still leave sensitive files in your Downloads folder.

Optional accounts on TechDriven Tools, when used, are about lightweight usage metadata — not storing the contents of your Image Resizer inputs.

If policy requires a vendor DPIA for any online tool, note that local browser processing reduces data transfer risk, but downloaded artifacts still need handling under your retention rules.

Image Resizer is built to process locally in your browser so sensitive PDFs, images, or text do not need to be uploaded to an unknown server just to finish this job.

Common mistakes

  • Upscaling tiny images — Enlargement cannot invent real detail.
  • Forgetting aspect lock — Stretched faces look unprofessional.
  • Resizing the archival original in place — Save as a derivative filename.

Getting reliable results from Image Resizer

Most failures with Image Resizer are input/setting issues rather than mysterious bugs: wrong units, wrong page lists, wrong language, or expecting one tool to do a sibling’s job. Re-read the option names, fix the input, and re-run — local tools make iteration cheap.

Image Resizer accelerates the workflow; it does not replace your judgment or professional advice where required.

These related tools commonly sit before or after Image Resizer in real workflows.

  • Image Compressor — Shrink one or many JPG/PNGs at a quality you choose — multi-file ZIP.
  • WebP Converter — Convert one or many JPG/PNGs to WebP — batch downloads as ZIP.
  • JPG to PNG — Related browser-local tool on TechDriven Tools.

Use Image Resizer when you need this specific job done privately and quickly. Respect what it is not (see mistakes), verify outputs, and chain related tools only when the next step truly differs.

Start from Image Resizer.

If you arrived from search looking for Image Resizer, bookmark the tool page itself after this guide — the article exists to teach options and pitfalls, not to replace the working UI.

When something looks wrong in Image Resizer, reproduce with a tiny sample input first. Smaller fixtures debug faster than a 200-page scan or a 2MB JSON blob.

Share feedback with teammates as option recipes (“Quality 72%, bottom-center numbers, Start at 1”) rather than screenshots alone — recipes transfer cleanly.

From our blog: How to Resize an Image for Web, Email, or Print