How do I add sound effects to a video online?

Upload your video to Valmera and ask in plain English: "add a whoosh at every cut", "put a boom on the title reveal", "add a riser building into the drop". The agent places the effect at the exact moment and mixes it with your music and speech. No effect libraries to search, no files to drag onto a timeline.

Can AI generate a sound effect from a text description?

Yes. Describe the sound — "a deep cinematic boom with a long tail", "a soft camera shutter click" — and Valmera generates a custom one-shot between 0.5 and 22 seconds long, then places it in your edit in the same request. If the built-in pack already covers it, the agent can use that instead, which costs less.

What sound effects are built into Valmera?

There's a built-in pack of 18 one-shot effects covering the workhorses of short-form editing: whooshes, impacts, risers, clicks, booms, dings, and more. You never browse the pack directly — you ask for the effect and the agent picks and places the right one.

What is a sound-design pass in video editing?

It's the finishing step where an editor adds the sounds that make cuts feel intentional: transition whooshes, an impact to punctuate the key line, a riser that builds tension into the climax. In Valmera it's one request — "do a sound-design pass" — and the agent places whooshes at your cuts, an impact on the strongest word, and a riser into the energy peak, based on an actual audio analysis of your video.

Is there a free AI sound effects generator without a watermark?

Valmera's free plan includes 20 credits every day plus a one-time 150-credit welcome bonus, no credit card required. On Free, a small Valmera mark sits in the corner of your export; on Plus and Pro there is no watermark at all. Every export closes with a brief (~2.5-second) Valmera end card after your video.

Can it generate background music too?

No — Valmera does not generate AI music or songs, and we say so plainly. For music you get a built-in library of 24 royalty-free CC0 tracks across 8 moods, plus your own uploads. Generation is for sound effects: one-shots up to 22 seconds, not full tracks.

How much does generating a sound effect cost?

Valmera charges credits in proportion to the work actually done in each request — there's no flat per-effect price. Placing a built-in one-shot is among the cheapest edits; generating a custom sound costs more because a generation model runs. The free plan's daily credits are enough to try both.

AI Sound Effects Generator

Valmera puts sound effects into your video by request: 18 built-in one-shots — whooshes, impacts, risers, clicks, booms, dings — a one-request sound-design pass, and AI generation that turns a text description into a custom effect between 0.5 and 22 seconds. Everything lands inside the edit: on the cut, on the strongest word, or building into the energy peak.

That's the difference from SFX download sites: nothing to search, download, or align by hand. You describe the sound and where it belongs; the agent does the placing and the mixing.

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Upload a video and ask for a whoosh, a boom, or a full sound-design pass. No credit card required.

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How to Add AI Sound Effects to a Video

1
Upload your video
Drag in any video up to 2GB (up to 3 hours). Valmera analyzes it once with visible progress — including the audio, so the agent knows where your cuts, emphasized words, and energy peaks are.
2
Type the request
Type something like "add a whoosh at every cut", "do a sound-design pass on the whole video", or "generate a deep cinematic boom and put it on the title reveal". The agent picks a built-in one-shot or generates the sound, then places and mixes it.
3
Preview, refine, export
Watch the preview, then adjust in plain English — "make the impact hit harder", "move the riser earlier". Export a full-quality MP4 rendered from your original upload, with only a small corner mark on the free plan.

The upload is analyzed once with visible progress; after that, each sound-effect change is a single chat message.

18 Built-In Sound Effects, Placed by Request

The core of the tool is a pack of 18 one-shot effects that covers most of what short-form editing actually uses: whooshes for transitions, impacts for punchlines, risers for tension, clicks, booms, and dings for UI moments and reveals. You never dig through a library — "add a whoosh at every cut" or "put a ding when the price appears" is the entire workflow, and the agent chooses the right one-shot and mixes it against your speech and music.

Placement is the point. Because Valmera already analyzed your video, an effect can target a cut, a specific word, or a timestamp — not just "somewhere around 0:12".

The One-Request Sound-Design Pass

If you don't want to art-direct each effect, ask for a sound-design pass and the agent does the finishing work an editor would: whooshes at the cuts so transitions feel deliberate, an impact on the strongest word so the key line lands, and a riser building into the energy peak so the video has shape. It's driven by Valmera's audio perception — the system actually detects your most emphasized words and the track's energy, rather than sprinkling effects at random.

It layers cleanly with the rest of the audio stack: background music that ducks under speech, per-layer volume, and a one-request master to −14 LUFS — details in the audio and music docs.

Describe Any Sound — AI-Generated SFX

When the pack doesn't have it, describe it. "A heavy metal door slamming in a cathedral", "an old film projector rattling to a stop", "a soft airy swell" — the AI generates a custom one-shot between 0.5 and 22 seconds from your text description and drops it into the edit in the same request. Each generation charges credits by its actual cost, so simple placements of built-in sounds stay cheap and you only pay generation prices when a model actually runs.

Generated sounds behave like any other layer afterwards: reposition them, change their volume, or remove them with a follow-up message.

Generated and Placed in the Same Editor

Standalone SFX generators hand you a file; the placement, timing, and mixing are still your problem. Valmera closes that loop because the generator lives inside an agentic editor that has already analyzed your footage: the sound is created, aimed at the right moment — a cut, the strongest word, the build into the peak — and mixed under or around your speech in one request. And the honesty layer verifies every reply against the edits actually made, so "I added the boom at 0:14" is a checked fact, not a guess.

Honest Limits: One-Shots, Not Songs

Sound-effect generation makes one-shots up to 22 seconds — it does not compose music, and Valmera has no AI music or song generation at all. For a soundtrack, use the 24-track CC0 library or your own uploads on the add-music side. And if your original footage has messy audio baked in, effects won't fix that — but you can mute the original audio and rebuild the soundtrack from music, effects, and a voiceover.

More Than a Sound Effects Generator

Sound design is one request among many. The same agent cuts silences and filler words, styles word-accurate captions, adds music and transitions, reframes for vertical, and grades the color — browse all the AI video editing tools to see the full set.

Frequently Asked Questions

Make It Sound Edited

Whooshes, impacts, risers — described in a sentence, placed on the moment. Free plan, no credit card.

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