What is the difference between compression levels?

Low re-packs the file structure without quality loss. Medium and High rasterize pages to JPEG at progressively lower quality — smaller file, less crisp.

Will text stay selectable after compression?

Only with the Low level. Medium and High rasterize pages, converting text to pixels.

Is there a file size limit?

No server limit — your browser's available memory is the only constraint. Very large PDFs may take a minute on Medium or High.

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CPU local
Hors-ligne possible
Nettoyage automatique

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convert / Compresser

Compresser

Réduire la taille en ré-échantillonnant les images.

Ajoutez au moins un PDF dans le bac à fichiers pour commencer.

Explorer d'autres outils

Méthodologie & Transparence Technique

Bibliothèques utilisées

pdf-lib — Logique principale de construction et d'édition PDF
pdf.js — Rendu PDF et rastérisation des pages

Stratégie mémoire

Après chaque opération, URL.revokeObjectURL() est appelé immédiatement. Tous les handles de documents pdf.js sont détruits via pdfDoc.destroy(). Les workers sont terminés à la fin du traitement ou au démontage du composant.

Nous ne garantissons pas la conservation permanente des fichiers (puisque nous ne les stockons pas). Le traitement local des PDF protégés par mot de passe n'est pas pris en charge.

Key Features

Three compression levels
Low (lossless re-save), Medium (1.5× JPEG rasterization), and High (1× JPEG) — choose the right trade-off.
Size reduction stats
After compression, the tool shows original size, compressed size, and percentage saved.
Lossless option available
The Low level uses object-stream packing — text stays fully selectable and vector graphics are not degraded.

Common Use Cases

Valuable for shrinking PDFs before emailing (most services cap at 10–25 MB), uploading to document portals with size restrictions, or reducing storage footprint for archival.

Frequently Asked Questions

What is the difference between compression levels?: Low re-packs the file structure without quality loss. Medium and High rasterize pages to JPEG at progressively lower quality — smaller file, less crisp.
Will text stay selectable after compression?: Only with the Low level. Medium and High rasterize pages, converting text to pixels.
Is there a file size limit?: No server limit — your browser's available memory is the only constraint. Very large PDFs may take a minute on Medium or High.